Festival of Britain

The Festival of Britain was a national exhibition which opened in London in May 1951 to boost national morale, as Great Britain was still recovering from World War II. The Doctor and Ace visited the Festival after defeating the Timewyrm. (NA: Timewyrm: Exodus) The Doctor also visited the Festival and saw his past self, but neither recognised the other. (EDA: Endgame)

In an alternate timeline in which Germany won the war, the Festival of Britain was a celebration of ten years of Nazi victory. The Doctor and Ace visited this version of the Festival, where they realised that history had been altered, and went to work preventing this timeline. (NA: Timewyrm: Exodus)