Is there anywhere further from London that gets more frequent trains to London? I looked the other day and it was something like a train every three minutes!
If Wikipedia is correct, East Croydon is 10.35 miles from London Bridge and gets 24 TPH to London: 11 to Victoria, 9 to London Bridge, 4 through Thameslink
I thought that Heathrow Terminals 1, 2, 3 (14.54 miles from Paddington) would beat this if you included the Piccadilly line services, but it only gets 16 TPH (again according to Wikipedia)