The exhibition was held in Wembley Park. It was a showcase of aspects of many of the British colonies at the time. It had 18 million visitors in 1924, but failed to break even. The main stadium was retained until 2003, when it was demolished and replaced by the current Wembley Stadium.
Opened on 23 April which just happens to be St George's Day and also the deathday and (likely and generally used) birthday of Shakespeare - all in all, the peak of calendarial Britishness.
This map shows the area used by the Exhibition: from the A479 in the west, to the River Brent in the east; from the Metropolitan Line in the north to the main line just south of the stadium in the south. The site was served by two 'Exhibition Stations': Wembley Park and (what is now) Wembley Stadium.
Credit for this entry to: Alan Patient of www.plaquesoflondon.co.uk
