 Complete the following phrase:  In 1924 and 1925, the British Empire Exhibition was held on the Wembley Park Estate and the adjacent Wembley Park station was rebuilt with a new island platform with a covered bridge linking to the exhibition. The Met exhibited an electric multiple unit car in 1924, which returned the following year with electric locomotive No. 15, subsequently to be named Wembley 1924. A national sports arena, Wembley Stadium was built on the site of Watkins Tower. With a capacity of 125,000 spectators it was first used for the 