The Backs is the stretch of riverbank behind the great colleges — King's, Clare, Trinity, St John's, Queens' — where their lawns and gardens run down to the River Cam through a succession of ornamental bridges. It is Cambridge's signature landscape: weeping willows trailing in the water, punts drifting past college walls, cows grazing on Coe Fen to the south. In summer it is genuinely beautiful and very crowded; in early morning or on a grey winter day it has an entirely different and arguably better quality.
You can walk the Backs along the public footpaths or experience it from the water by punting. The footpaths are free and open. The most photogenic views are from the bridges: Queens' Bridge (the so-called Mathematical Bridge), Clare Bridge (the oldest in Cambridge, 1638), and the Bridge of Sighs at St John's.