[Jonesy55]

Paris actually has more people commuting from longer distances than London does from figures I've seen. Probably because there are fewer surrounding mid sized cities as alternatives. Surrounding London are Brighton, Portsmouth, Southampton, Reading, Oxford, Milton Keynes, Cambridge which all have reasonable employment markets so people living in or close to those places usually work there rather than in London. Plus UK rail season tickets in the SE are expensive so that's another factor making more people work locally to where they live.