Founded in 1441 by Henry VI and the earliest of the royal foundations, King's College is worth visiting for the huge expanse of lawn extending down to the river and King's Bridge, with its lovely views of the Backs, the various college grounds along the riverside. 

Distinguished alumni includes writer Horace Walpole, poet Rupert Brooke, and economist Lord Keynes.

A must-see here is King's College Chapel, renowned for its 12-bay perpendicular-style interior, as well as its breathtaking fan vaulting by John Wastell (1515)