Enjoy a waterside cycle or walk around the pretty Linford Lakes Nature Reserve in Milton Keynes. At the site you will find a large lake, woodland, small meadows and a series of ponds and smaller lakes. You can stop on the way and enter one of the bird hides where you can look out for Waterfowl, Waders, Heron and Egret. In the woodland section you make catch a glimpse of the Reeves Muntjac Deer. There's also sections along the Grand Union Canal and the River Great Ouse. To get full access to the reserve you need a permit from http://www.theparkstrust.com/parks/linford-lakes-permit.
If you would like to continue your exercise you could enjoy more waterside walking along the Grand Union Canal or head to the nearby Willen Lake.