This month’s photograph shows a group attending the Trinity May Ball in 1905. They are posed around the water fountain in the Market Place. College May Balls traditionally happen, not in May, but in June at the end of the exam period.
The ball at Trinity College is the first to take place and is officially known as the First and Third Boat Club May Ball. The first official ball took place in 1866 to celebrate the success of the First and Third rowing teams at the May Bumps (a rowing competition which still takes place annually).
For more on the Bumps see the website of the Cambridge University Combined Boatclubs.