Medalet - George V and Mary British Empire Exhibition Wembley

The British Empire Exhibition was a colonial exhibition held at Wembley, Middlesex in 1924 and 1925.[1][2][3][4] A highlight was the elaborate "Pageant of Empire" with thousands of actors.
It was opened by King George V on St George's Day, 23 April 1924. The British Empire contained 58 countries at that time, and only Gambia and Gibraltar did not take part. It cost £12 million and was the largest exhibition ever staged anywhere in the world - it attracted 27 million visitors.
Its official aim was "to stimulate trade, strengthen bonds that bind mother Country to her Sister States and Daughters, to bring into closer contact the one with each other, to enable all who owe allegiance to the British flag to meet on common ground and learn to know each other". Maxwell Ayrton was the architect for the project. The three main buildings were the Palaces of Industry, Engineering and Arts. The Palace of Engineering was the world's largest reinforced concrete building, a building method that allowed quick construction.
A special railway loop line and station were built, to connect the site to London Marylebone station. The various buildings of the site were linked by several 'light railways', including the screw-driven 'Never-Stop Railway'.
https://en.wikipedia.org/wiki/British_Empire_Exhibition