The original Debating Hall (now the Old Library) was built in 1857. In the spring of 1858 William Morris, Dante Gabriel Rosetti and others started work on its extensive murals, all the designs being based on the legend of King Arthur. These were restored in 1986.
A new hall was built in 1878 and includes busts of Asquith, Gladstone, Salisbury, and Lord Curzon (all former officers of the Union).