Found one: https://maps.google.co.uk/maps/ms?msid=205219750117388122373.0004ab5541d175f40fc24&msa=0&dg=feature
@J0nathan started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
Found one: https://maps.google.co.uk/maps/ms?msid=205219750117388122373.0004ab5541d175f40fc24&msa=0&dg=feature