There are some surprisingly scenic walks in the countryside between the prosperous commuter village of Downe, which has handsome houses and a couple of pubs, and the M25. From Downe, take the B road towards Biggin Hill and then pick up one of the footpaths south west, towards the hamlet of Cudham. Soon you'll be descending down a steep path through the pleasant woods into a large and luscious valley, empty except for a substantial wood-beamed farmhouse and a few outbuildings. Only the occasional two-seater plane, heading back to Biggin Hill, might disturb the peace.
It is quite a steep climb from the valley floor up into Cudham, but the Blacksmith's Arms has some tables at the front where you can slake your thirst and soak up the afternoon sun. Suitably refreshed, cut through the churchyard and follow the yellow arrows across the fields veering north (head towards the distant towers of Canary Wharf). If you don't want to do the full circular walk (up to eight miles), look for a footpath east, which will take you back across the valley, before climbing through the woodland nature reserve. It won't be long before you'll hit a B road. Find the scenic footpath on its eastern flank and follow it back north into Downe. 8/10