Comment by rsynnott

It likely depends how you're defining separated. Some cities go for completely separate routes, some curb separation, some bollard separation, some on-footpath separation. Some use a chaotic mix (Dublin, say, is building a 300km segregated system, but because this is being delivered by seven local authorities plus the National Transport Authority, it is a mix of seemingly every possible solution, including weird stuff like contraflow bike lanes, and bike lanes between on-street parking and the footpath).