The Regent’s Canal
I’ve known the Regent’s Canal, which describes a 200 hundred year old, East-West arc through London just to the north of the centre, for many years.
When I worked on the northern edge of the city of London, it was easy to reach for a lunchtime jog. It is also part of the least stressful route for cycling from further north to Limehouse, where the canal joins the Thames, and thence through Canary Wharf down to the Greenwich Foot Tunnel (firebombed in the zombie film 28 Weeks Later).