University College, Oxford—known as “Univ”—is one of Oxford’s oldest and most historic constituent colleges, dating back to 1249 and located centrally in the city. It is perhaps the oldest College with rumours it dates in part to 849 although this is unlikely. 
Notable figures associated with Univ include Clement Attlee, Harold Wilson, Bill Clinton, Stephen Hawking, C. S. Lewis, V. S. Naipaul, and Percy Bysshe Shelley.
 
Interesting fact...
In the 1940s, Sir Ernst Chain, co-discoverer of penicillin and Nobel laureate, wished to become a member of University College but was not admitted—a secret regret for the college in hindsight