Not car free but i can definitely tell you there is possibility to walk, public transit in MOST of EU cities. Starting from Scandinavia, almost any city with pop , 10k or more will have generally bus transport, and probable connectivity to nearest big city by train/bus, big cities have metro (Stockholm) that I know of Germany has vast network of rail(although it’s schisse at moment with DB) , within cities its bus , that I know of . France almost any big city will have bus, tram and/or metro and long distance trains Same for spains cities , Netherlands is famous for its Public transport This is from what I know

Cars are severely slow and given less prio in these countries, in any of big city e.g. Barcelona, Paris, Hague, you can see you can go faster by public transportation or almost same time as car for same destinations , check it out in Google maps with comparisons