Comment by ClumsyPilot

Important background: Building the same tram in Britain costs at least 2X more than in France, often 3x more.

UK tram track construction typically involves deeper track beds compared to France/EU, using concrete slabs of 500-1000mm deep, is intended to protect utilities. In contrast, many European projects utilize shallower trackbeds, even with grassed areas, which are 300-400mm deep