London Circle Walk: Circle the city on an epic 20-mile hike

One of London's more peculiar communities is the London Circle Walk. This special walking group meets once a year to embark on a 20-mile circular route of London, walking down the city streets and alleys to draw a near-perfect circle on the map.

The London Circle Walk was devised years ago over pints by a pair of enthusiasts who mapped out the route, which is positioned around the official centre of London, the statue of Charles I at the top of Whitehall. The circumference of the route is determined by the places where you can cross the Thames while still being able to finish the walk in one day. The annual Circle Walk starts at the middle of Tower Bridge and heads clockwise, reaching its southernmost point at Stockwell before zigzagging up through to Battersea Park, crossing the Thames via the Albert Bridge, then reaching the halfway point at Kensington Gardens. From there, it's up through Regent's Park and Camden Town to King's Cross, before heading back down to Tower Bridge via Shoreditch and the City of London. Though the object of the exercise is not sightseeing, there are plenty of interesting things to see along the route, from major landmarks to local sights you might never even have heard of.

All are welcome to join the London Circle Walk, which meets this Saturday, 21 September at 9.45am in the middle of Tower Bridge on the east side. As the adventure takes the whole day, you're advised to bring appropriate footwear and clothing, as well as snacks and drinks. There will also be a lunch stop around the halfway mark.