It would be neat if it there were an option which added distance and elevation gain, but minimized the grade.
For example, a route from SOMA to Nob Hill can be made flatter by approaching from either the east or west. Technically the "flattest" as measured by elevation gain between the two is straight up Taylor from Market, but it's much nicer to bike to the top of Nob Hill by going out of the way (e.g. Polk → California, Embarcadero → Broadway, etc.)
I suspect that this would result in absurdly long routes. Imagine trying to go up a mountain while minimizing grade... you'd end up zig-zagging back and forth endlessly.
Isn’t that exactly how you build a trail up a mountainside? They are usually a series of switchbacks.
Most people on most bikes can only take so much grade before climbing becomes impossible. A maximum grade setting would be very helpful for that exact reason.
Unless you are on foot (and even then) the route needs to follow existing roads, you can only zig zag as much as existing roads do it not endlessly.
And almost any practical routing system will have a mechanism for tradeoffs of different aspects. Often there is a distance/time tradeoff which directly relates to speed on corresponding segments. But the tradeoff can also be in the form of "on average x seconds spent waiting green light in each intersection or time to stop before railroad crossing. So there is no reason for a system optimizing grade to completely ignore all other factors, it's just a question of weights and curves of each of them.
Like the ascent to Mt. Hamilton (southern Bay Area). You can see the peak for like an hour but so much twisting back and forth, going mostly perpendicular to the max gradient. It is an old road and hence graded for mules to carry up telescopes.
It's not accurate. I mapped it from my house on Cabrillo St in the outer Richmond to 4th avenue and it says I need to climb 25th avenue then walk Geary instead of correctly telling me to use 23rd avenue that is completely flat.
ah, I think this is related to SF's "Slow Streets" program and a genuine bug in the parser.
Cabrillo is a Slow Street, and the parser read its "destination-only" tag as closed to pedestrians, so the tool couldn't see the street at all (and started you a block over?). fixed and deployed; your trip should now go Cabrillo → 23rd → Geary.
There's a weird thing going on at 22nd and San Jose in the Mission, where it doesn't seem to understand that you can simply continue down 22nd, but instead takes a hook down San Jose before backtracking. I see some other weird discontinuities like this as I click around.
I have to say that the Claude UI has made many inexplicable decisions here, including (but not limited to) the mysterious color coding, the confusing continuous slider over a discrete set, and the weird positioning of the height labels in the altitude graph.
This is great. Since SF is mostly a grid, I used to use the heuristic of only choosing paths that wouldn't take me further from my destination, avoiding going downhill but choosing the shallower uphill climb if a choice is given.
Other than knowing the direction of my destination, it only used local information
Nice visualization. For proper turn by turn directions, Valhalla [1] could help. It has elevation support so this could theoretically be built with it[2], or you just send the shape of your flattest route and it annotates it with guidance.
This seems to have the same issue I saw with Google Maps where it directed me along 29th St from near Mission Bernal Safeway to Diamond Heights Safeway. This includes a 22.7% grade! It's much faster and easier (at least on my cargo e-bike) to take the longer way around up Clipper St (12% grade).
The bug seems to be apparent when you set the end point at Duncan & Diamond Heights Blvd and the start point directly north along Clipper.
This route seems to maybe save 1 ft of climbing but goes up a 23% grade.
Something like this would be useful in Istanbul Taking into account public transportation and then minimizing elevation changes for the walking portion. That is one very hilly city.
This is really cool! I tried it with my old address (xywz 24th Street) and it doesn't accept it for some reason. I was able to try it from 24th and Mission BART however.
thanks! address search uses the overture address feed, which is patchy (some blocks of 24th st have 5 numbers in it)… i'll make it fall back to the nearest known number on the street
I wonder how that would work here with horribly inaccurate elevation data. I often ride a specific flat straightaway and Strava and other tracking apps always show me pedaling up and down 20-meter pine trunks next to the bike path.
I was wanting something similar to see the fall leaves in the mountains of NC. I wanted to pick roads at the appropriate elevation, where they are in peak, but google maps isn't really geared for that.
I've been making an app similar to this but for pedestrians. I live in a very hilly city, and google maps will give you the shortest distance between 2 points, but that may involve climbing and descending steep hills even across short distances.
Any savvy resident however knows the location of escalators, lifts and metro stops to bypass that, and all have different allowed times of access and operation.
Once I was visiting Yamaha’s Yokohama office for work, and I found a pedestrian path from my hotel to the office of ~2.5km that never touched a single roadway…
Google Maps absolutely failed.
Would be fun to rig up something for these cities. Which are you in btw?
It’s interesting that the big tech companies are all in the hilly Bay Area and yet the native mapping apps are fairly ignorant of hills impact on travel times.
Sure Apple Maps tells me there’s qualitatively that there are hills on my walking route, but the estimated walk time seems hilariously optimistic once I start walking around a hilly city. For reference I’m a fast (15min or less per mile NYer) walker normally.
For example I just input a 1/2 mile walk down a steep hill and the return walk. The estimated walk time was 10min down and 11min up. These estimates are far too close to each other and far too close to default flat walk estimates in Apple Maps.
Your net elevation change is just the difference in altitude between your starting point and your ending point. So yes, it’s independent of route, but that’s not what the term “climb” refers to. It’s not a net elevation change; it’s a cumulative elevation gain, because in bicycling and walking the in‑between parts burn energy. Human legs don’t have regenerative braking, so every time you gain a foot of altitude you don’t get those calories back when you lose a foot of altitude.
In addition, while the net elevation change is bounded by the delta, given the choices might be "go up this steep section" vs "go along this gentle incline", one route can be "flatter" between the same endpoints.
When I used to ride around SF on an e-bike, I’d deliberately choose undulating routes so I could climb at max assist speed and then fly down the descents above max assist speed.
As a life-long city cyclist, with a fable for going fast while staying pedantically lawful, I found that my prefered routes are not about avoiding hills, but about:
1. The length of uninterrupted high quality bicycle ways (e.g. no traffic lights crossings etc.), a 2 km uninterrupted path beats a 1 km route with a ton of crossings and traffic lights
2. The quality of the bicycle path surface. I accept a slightly longer path if the road surface doesn't resemble a moon landscape
3. The potential for "chaos" (for a lack of better words) on that route. For example I will take a detour if it avoids going through areas with tourists and taxis, all of whom appear to be surprised by the concept of the bicycle on a bicycle path on a deep existential level.
Of course hills can play a role as well, but that may be more important in some cities than others.
In my experience, Google Maps too often sends me down dangerous streets - busy, wide, arterials with fast moving automobiles.
Though I do know some people who prefer them because they can be a little faster. Not worth it for me. I'd much rather go a little out of my way for a comfortable safe ride.
Checkout https://bikehopper.org for solid elevation, bike infrastructure and transit-aware routing around the Bay Area. Some friends and I built this about 5 years ago and continue to maintain it. We use 1m DTM elevation data for SF and 50m for rural areas. DTM is a must for elevation based routing in SF as there are so many sizable buildings, large trees the other models fail hard.
I've checked out a few bike mapping apps recently and one feature I found absolutely invaluable was grade indications like http://hillmapper.com (which unfortunately seems unmaintained.)
Google Maps elevation diagrams comparing the various selected routes are nice but they do not do a good job of highlighting extreme grades. I feel like you actually want to graph the change in elevation rather than the elevation itself.
Using a route I cycled the other day (near Mission Bernal Safeway to near Diamond Heights Safeway). I think the routing may overweight bike lanes too much. For instance it will go four blocks by shared street and bike lane to avoid the two blocks on Clipper between Sanchez and Castro which are not a bike lane.
On my heavy cargo e-bike I've found there is quite a non-linear difference as the grade increases. 12% and I'll work a bit but be fine. 22% (the route Google Maps sent me...) and I'll all but collapse after a block.
Hillmapper falling apart was one of the main reasons we prioritized getting good elevation data into our router. We include steepness indicators for steep blocks and an elevation overview of the full trip and have found that combo to serve us well.
Getting between those two Safeways is rough. Bikehopper fails, it suggests the harry street steps; a non-starter for most. I’ll try to fix it. I definitely agree that grade is non-linear. We use accelerating weighting for grade so a hill that is twice as steep is more than twice as “discouraged” by the routing engine.
For bike routing I think e-bikes need a separate profile from acoustic bikes. Hill matter less and stairs are totally out of the question (this is important for routing in and out of transit centers).
Can you please consider expanding it to include Seattle? Or better yet Puget Sound area? 1m DTM elevation data is available here. We have many amazing bike trails, but also plenty of hills that must be avoided.
We’d like too! It’s an open source project that was never designed to scale beyond one regions (bay area, puget sound, NYC, etc…) our hope has always been been that folks in different regions would spin up their own copy. By keeping it regional the data and hardware requirements for running it are minimal. That said, we are working on a new routing engine that we hope can scale to support continent wide routing. Then we can manage running it for many metro’s. If you’re interested in self hosting for Seattle we are happy to help get it set up.
DSM includes buildings and trees. So the DSM from SRTM data makes market street in S.F. look like a series of very steep hills and valleys because some of the datapoints are street level while others are the roofs of skyscrapers. DTM removes the buildings resulting in a map much closer to what we think of from the ground.
It's interesting (and unsurprising I guess) to see that bike lanes in the US are much like those in the UK - a line on the road, rather than real segmentation.
They are a real segmentation in some places but as you can probably guess that is few and far between. A line on the road is also in the minority with the rest being nothing at all.
It would be neat if it there were an option which added distance and elevation gain, but minimized the grade.
For example, a route from SOMA to Nob Hill can be made flatter by approaching from either the east or west. Technically the "flattest" as measured by elevation gain between the two is straight up Taylor from Market, but it's much nicer to bike to the top of Nob Hill by going out of the way (e.g. Polk → California, Embarcadero → Broadway, etc.)
I suspect that this would result in absurdly long routes. Imagine trying to go up a mountain while minimizing grade... you'd end up zig-zagging back and forth endlessly.
Isn’t that exactly how you build a trail up a mountainside? They are usually a series of switchbacks.
Most people on most bikes can only take so much grade before climbing becomes impossible. A maximum grade setting would be very helpful for that exact reason.
9 replies →
Unless you are on foot (and even then) the route needs to follow existing roads, you can only zig zag as much as existing roads do it not endlessly.
And almost any practical routing system will have a mechanism for tradeoffs of different aspects. Often there is a distance/time tradeoff which directly relates to speed on corresponding segments. But the tradeoff can also be in the form of "on average x seconds spent waiting green light in each intersection or time to stop before railroad crossing. So there is no reason for a system optimizing grade to completely ignore all other factors, it's just a question of weights and curves of each of them.
Like the ascent to Mt. Hamilton (southern Bay Area). You can see the peak for like an hour but so much twisting back and forth, going mostly perpendicular to the max gradient. It is an old road and hence graded for mules to carry up telescopes.
well. That or a nice spiral! :)
It's not accurate. I mapped it from my house on Cabrillo St in the outer Richmond to 4th avenue and it says I need to climb 25th avenue then walk Geary instead of correctly telling me to use 23rd avenue that is completely flat.
I think this comes down to the DEM they are using. I think it would have come out better if they had used USGS 3DEP DTM at 25cm.
Edited: which apparently is hosted for free on AWS S3.
ah, I think this is related to SF's "Slow Streets" program and a genuine bug in the parser.
Cabrillo is a Slow Street, and the parser read its "destination-only" tag as closed to pedestrians, so the tool couldn't see the street at all (and started you a block over?). fixed and deployed; your trip should now go Cabrillo → 23rd → Geary.
“genuine bug in the parser” -> red flag for slop for those keeping track at home
4 replies →
This is super cool! The map and UI are super clean, well done!
This makes me want to take out my longboard.
The wiggle!
(in honor of my old commute, which I miss)
https://flattensf.com/#t~-122.40850~37.77493~-122.50940~37.7...
There's a weird thing going on at 22nd and San Jose in the Mission, where it doesn't seem to understand that you can simply continue down 22nd, but instead takes a hook down San Jose before backtracking. I see some other weird discontinuities like this as I click around.
I have to say that the Claude UI has made many inexplicable decisions here, including (but not limited to) the mysterious color coding, the confusing continuous slider over a discrete set, and the weird positioning of the height labels in the altitude graph.
This is great. Since SF is mostly a grid, I used to use the heuristic of only choosing paths that wouldn't take me further from my destination, avoiding going downhill but choosing the shallower uphill climb if a choice is given.
Other than knowing the direction of my destination, it only used local information
It's telling me to bike on Geary and Divisadero. No thank you I'd rather stay alive.
fair point! it just doesn't know about bike lanes yet, I’ll see about getting the SFMTA bikeway network map from DataSF.
Nice visualization. For proper turn by turn directions, Valhalla [1] could help. It has elevation support so this could theoretically be built with it[2], or you just send the shape of your flattest route and it annotates it with guidance.
[1]: https://github.com/valhalla/valhalla
[2]: Currently it only supports 30m resolution for elevation unfortunately
This seems to have the same issue I saw with Google Maps where it directed me along 29th St from near Mission Bernal Safeway to Diamond Heights Safeway. This includes a 22.7% grade! It's much faster and easier (at least on my cargo e-bike) to take the longer way around up Clipper St (12% grade).
The bug seems to be apparent when you set the end point at Duncan & Diamond Heights Blvd and the start point directly north along Clipper.
This route seems to maybe save 1 ft of climbing but goes up a 23% grade.
https://flattensf.com/#t~-122.43968~37.74865~-122.44028~37.7...
Half a block up the street it takes the sensible route with only a 13% grade. (Between the two different starting points is 41ft of climbing.)
https://flattensf.com/#t~-122.44087~37.74864~-122.44028~37.7...
good point.. the slider trades distance against total climbing and nothing else. steepness is currently reported but not optimized.
seems like a worthy addition to the objective!
Something like this would be useful in Istanbul Taking into account public transportation and then minimizing elevation changes for the walking portion. That is one very hilly city.
If that's OpenStreetMap data, it is missing the required attribution.
It shows "Streets © Overture / OpenStreetMap · Elevation USGS 3DEP" in the bottom right.
There’s the attribution at the bottom-right corner.
Thanks. Not visible on mobile here.
Would love an option for the steepest route! I run a lot in SF and try to maximize vertical gain on my routes
This is really cool! I tried it with my old address (xywz 24th Street) and it doesn't accept it for some reason. I was able to try it from 24th and Mission BART however.
thanks! address search uses the overture address feed, which is patchy (some blocks of 24th st have 5 numbers in it)… i'll make it fall back to the nearest known number on the street
Or just https://brouter.de/ with min elevation profile.
Absolutely love the live profile updating when you swipe from flatter to shorter.
Cool, I used to build this https://github.com/cheeaun/steepless (2014)
I wonder how that would work here with horribly inaccurate elevation data. I often ride a specific flat straightaway and Strava and other tracking apps always show me pedaling up and down 20-meter pine trunks next to the bike path.
Flattest or most level? They're different, but related measurements.
A surface can be flat while still increasing or decreasing in relative elevation.
With flat being like a line, level is defined as a line along the same elevation, right?
Therefore, a route can only be level if start and end point are at the same elevation and there is a flat/level road between them.
Flat is an opt description for the goal here. Like you mention, with elevation gain between the points we can still try to find a flat route.
I was wanting something similar to see the fall leaves in the mountains of NC. I wanted to pick roads at the appropriate elevation, where they are in peak, but google maps isn't really geared for that.
someone should make flattendallas.com as a joke
> The slider runs along the whole trade-off between distance and climbing [...] Climbing is cumulative gain
Another mechanism might be a kind of user-defined cost-curve, where a gradual climb to 10 might be preferred over a steep climb to 8, etc.
You want OpenTripPlanner. Their triangle lets the user trade distance, climbing, and safe facilities.
https://github.com/opentripplanner/OpenTripPlanner
https://github.com/opentripplanner/OpenTripPlanner/blob/dev-...
Or brouter with custom weights also has a lot of tuning points
This would be useful in Amsterdam, where bridges over canals are considered "mountains".
Amsterdam could use a route planner where you set the vehicle and it gives you the best route. The Netherlands now has:
- Bicycles
- E-bikes up to 25km/h and 250 watt (same as bicycle)
- E-bikes with wide tires (banned in certain areas)
- E-bikes going 45km/h (need to use car roads)
- Mopeds going 25km/h (need to use bicycle lanes, can't be in certain areas)
- Mopeds going 25km/h electric (similar, but can use more areas)
- Mopeds going 45km/h (need to use car roads)
- Motorcycle (need to use car roads, don't have privileges over cars other than filtering)
- Tractor / agricultural machine
- Mobility scooter (can use bicycle lanes, can absolutely not use car lanes)
- Mobility vehicle for people with a disability (can use most bicycle lanes and have more parking privileges)
- Electric wheelchair
- Light electric car / micro-car (can't use bicycle lanes, can use ferries)
- Tricycle usable with car license
- Tricycle useable with motorcycle license
And probably some more I forgot.
I've been making an app similar to this but for pedestrians. I live in a very hilly city, and google maps will give you the shortest distance between 2 points, but that may involve climbing and descending steep hills even across short distances.
Any savvy resident however knows the location of escalators, lifts and metro stops to bypass that, and all have different allowed times of access and operation.
Once I was visiting Yamaha’s Yokohama office for work, and I found a pedestrian path from my hotel to the office of ~2.5km that never touched a single roadway…
Google Maps absolutely failed.
Would be fun to rig up something for these cities. Which are you in btw?
You should consider adding drive as well, some of us have manual transmissions still, although the Bike mode returns pretty reasonable results.
Isn't this a bit like the "Is there alligators in the water?" test, yep its wet, there's alligators....Is the route SF hilly? yes!
It’s interesting that the big tech companies are all in the hilly Bay Area and yet the native mapping apps are fairly ignorant of hills impact on travel times.
Sure Apple Maps tells me there’s qualitatively that there are hills on my walking route, but the estimated walk time seems hilariously optimistic once I start walking around a hilly city. For reference I’m a fast (15min or less per mile NYer) walker normally.
For example I just input a 1/2 mile walk down a steep hill and the return walk. The estimated walk time was 10min down and 11min up. These estimates are far too close to each other and far too close to default flat walk estimates in Apple Maps.
they're probably made for people on cars. or who take transportation.
Sorry if this is a stupid question, but isn’t the climb independent of the route?
Your net elevation change is just the difference in altitude between your starting point and your ending point. So yes, it’s independent of route, but that’s not what the term “climb” refers to. It’s not a net elevation change; it’s a cumulative elevation gain, because in bicycling and walking the in‑between parts burn energy. Human legs don’t have regenerative braking, so every time you gain a foot of altitude you don’t get those calories back when you lose a foot of altitude.
My next E-Bike will hopefully have regenerative brakes for that reason, I hate to waste that energy.
Not if there are hills in between. But the delta between A and B is the best you can do, yes.
In addition, while the net elevation change is bounded by the delta, given the choices might be "go up this steep section" vs "go along this gentle incline", one route can be "flatter" between the same endpoints.
Honestly, when I drive around San Francisco, I really enjoy the hills.
I really miss driving down Gough ("Go").
Gradient Descent
When I used to ride around SF on an e-bike, I’d deliberately choose undulating routes so I could climb at max assist speed and then fly down the descents above max assist speed.
Cool! Any way to toggle on street names on the map?
As a life-long city cyclist, with a fable for going fast while staying pedantically lawful, I found that my prefered routes are not about avoiding hills, but about:
1. The length of uninterrupted high quality bicycle ways (e.g. no traffic lights crossings etc.), a 2 km uninterrupted path beats a 1 km route with a ton of crossings and traffic lights
2. The quality of the bicycle path surface. I accept a slightly longer path if the road surface doesn't resemble a moon landscape
3. The potential for "chaos" (for a lack of better words) on that route. For example I will take a detour if it avoids going through areas with tourists and taxis, all of whom appear to be surprised by the concept of the bicycle on a bicycle path on a deep existential level.
Of course hills can play a role as well, but that may be more important in some cities than others.
Lausanne residents play the same game, but with elevators, metros, bridges, stairs and Lime bikes as additional game mechanics. :)
I love Trick Dog!
Neat! Now find me some hills on my routes in Cambridgeshire, it's flat as a pancake out here
Doesn't Google Maps in bicycle mode already do this?
There are many constraints to satisfy, and avoiding hills is but one of them.
Most of us would take a hill with a protected bike lane over a flat 45mph.
In my experience, Google Maps too often sends me down dangerous streets - busy, wide, arterials with fast moving automobiles.
Though I do know some people who prefer them because they can be a little faster. Not worth it for me. I'd much rather go a little out of my way for a comfortable safe ride.
can someone build a similar one for Sydney?
now i need the steepest route for those downhill skateboard rides :)
you could mathematically find the least bikeable city using this lol
It’s all just the wiggle lol
Now do Houston (:->
Try downtown to somewhere in Bernal, say Progressive Grounds coffee house.
The flattest route is only 0.2 miles longer than the shortest, but goes from 200ft of climbing to 500ft of climbing, 12% max grade to 22% max grade.
Apple maps picks the shortest every fucking time.
Checkout https://bikehopper.org for solid elevation, bike infrastructure and transit-aware routing around the Bay Area. Some friends and I built this about 5 years ago and continue to maintain it. We use 1m DTM elevation data for SF and 50m for rural areas. DTM is a must for elevation based routing in SF as there are so many sizable buildings, large trees the other models fail hard.
Very Cool. Thanks for making it!
I've checked out a few bike mapping apps recently and one feature I found absolutely invaluable was grade indications like http://hillmapper.com (which unfortunately seems unmaintained.)
Google Maps elevation diagrams comparing the various selected routes are nice but they do not do a good job of highlighting extreme grades. I feel like you actually want to graph the change in elevation rather than the elevation itself.
Using a route I cycled the other day (near Mission Bernal Safeway to near Diamond Heights Safeway). I think the routing may overweight bike lanes too much. For instance it will go four blocks by shared street and bike lane to avoid the two blocks on Clipper between Sanchez and Castro which are not a bike lane.
On my heavy cargo e-bike I've found there is quite a non-linear difference as the grade increases. 12% and I'll work a bit but be fine. 22% (the route Google Maps sent me...) and I'll all but collapse after a block.
Hillmapper falling apart was one of the main reasons we prioritized getting good elevation data into our router. We include steepness indicators for steep blocks and an elevation overview of the full trip and have found that combo to serve us well.
Getting between those two Safeways is rough. Bikehopper fails, it suggests the harry street steps; a non-starter for most. I’ll try to fix it. I definitely agree that grade is non-linear. We use accelerating weighting for grade so a hill that is twice as steep is more than twice as “discouraged” by the routing engine.
For bike routing I think e-bikes need a separate profile from acoustic bikes. Hill matter less and stairs are totally out of the question (this is important for routing in and out of transit centers).
7 replies →
Can you please consider expanding it to include Seattle? Or better yet Puget Sound area? 1m DTM elevation data is available here. We have many amazing bike trails, but also plenty of hills that must be avoided.
Check out Modemix (modemix.io)
It's available in Seattle
In the meantime, you can check out maps.earth, which has bike+transit directions for the puget sound area (also sfbay, los angeles, portland)
...though the elevation model I'm currently using is courser (~30m, from Mapzen skadi). This is a good reminder to fix that where available!
Hit me up if you want to use the iOS beta which has some nice transit features (already available on the web).
We’d like too! It’s an open source project that was never designed to scale beyond one regions (bay area, puget sound, NYC, etc…) our hope has always been been that folks in different regions would spin up their own copy. By keeping it regional the data and hardware requirements for running it are minimal. That said, we are working on a new routing engine that we hope can scale to support continent wide routing. Then we can manage running it for many metro’s. If you’re interested in self hosting for Seattle we are happy to help get it set up.
6 replies →
Would a DSM not be preferable to a DTM? Or is that you reference with regards to large trees?
DSM includes buildings and trees. So the DSM from SRTM data makes market street in S.F. look like a series of very steep hills and valleys because some of the datapoints are street level while others are the roofs of skyscrapers. DTM removes the buildings resulting in a map much closer to what we think of from the ground.
It's interesting (and unsurprising I guess) to see that bike lanes in the US are much like those in the UK - a line on the road, rather than real segmentation.
They are a real segmentation in some places but as you can probably guess that is few and far between. A line on the road is also in the minority with the rest being nothing at all.
Allow me to plug my own SF microsite https://isitsunnyinthemission.com
Combine these two for the easiest bike ride to a sunny day
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