Furzton Lake - which is 1.8 miles to walk around, and has wide enough pathways to allow walkers, joggers and cyclists to peaceably co-exist. Similarly the network of "Redways" and linear parks allows pleasant and motor-traffic free walks - either to a specific place (I often walk the 2 miles from my home to Milton Keynes Central Rail Station - purely through parkland) or on a 'circular' route.
As well as being pleasant - and physically healthy - these walks offer an opportunity to learn more. I subscribe to a number of podcasts. The walk in the morning to the station gives sufficient time to listen to the overnight version of "Today in Parliament", and some of the previous evening's "Washington Today". During my walks around the lake I either listen to an audio book (from Audible - recent purchases have included "Master of the Senate"; Dallek on the American Presidency; Schrecker on McCarthyism "The Modern Scholar: American Inquisition) or one of the many C-SPAN podcasts .
Walks are also fantastic opportunities to think things through. Many ideas for Washminster posts arise and are developed on one of these walks. Minor episodes of "writers block" can also be ended that way.