The May Bumps (also May Races, Mays) are a set of rowing races, held annually on the River Cam in Cambridge, England. They began in 1887 after separating from the Lent Bumps, the equivalent bumping races held at the end of February or start of March. Prior to the separation there had been a single set of annual bumps dating from its inception in 1827. The races are open to all college boat clubs from the University of Cambridge, the University Medical and Veterinary Schools and the Anglia Ruskin Boat Club. The May Bumps takes place over four days (Wednesday to Saturday) in mid-June and is run as a bumps race.

Structure of the May Bumps

The races are run in divisions, each containing 17 crews. The number of crews in each bottom division varies yearly depending on new entrants. Each crew contains eight rowers and one coxswain. A total of 154 crews took part in 2014, totalling around 1390 participants. There are currently six divisions for men's crews (referred to as M1, M2...M6) and four divisions for women's crews (similarly W1–W4). The divisions represent a total race order with Division 1 at the top. The ultimate aim is to try and finish Head of the River (also said as gaining the 'Headship'), i.e. 1st position in division 1.

May Bumps

At the start, signalled by a cannon, each crew is separated by a distance of about boat lengths (approximately 30 m or 90 ft). Once the race has begun, a crew must attempt to catch up with the crew ahead of it and bump (physically touch or overtake) it before the crew behind does the same to them. A crew which bumps or is bumped must pull to the side of the river to allow all the other crews to continue racing. If a crew is able to catch and bump the boat which started three places in front of it, after the two in front have already bumped out, the crew is said to have over-bumped. A crew which neither bumps a crew ahead nor is bumped by a crew behind before crossing the finishing post is said to have rowed over.

May Bumps

After the race, any crew which bumps or over-bumps swaps places with the crew that it has bumped for the following day's racing. A crew which rows over stays in the same position. Crews finishing at the top of a division also start at the bottom of the next division, as the sandwich boat, in an attempt to try to move up into the next division. The process is repeated over four days, allowing crews to move up or down several places in the overall order of boats. The finishing order of one year's May Bumps are then used as the starting order of the following year's races.

May Bumps

Crews finishing Head of the River

Men's May Bumps (1887–2023)

May Bumps were cancelled between 1915 and 1918, and in 1940 due to war, and in 2020 and 2021 due to the COVID-19 pandemic. Prior to 1946 were two separate rowing clubs: 1st Trinity and 3rd Trinity, hence both separate and combined titles.

Women's May Bumps (1974–2023)

The Women's May Bumps were rowed in coxed fours between 1974 and 1989, changing to coxed eights from 1990 onwards. A new start order was used for the women's 1990 races. May Bumps were cancelled in 2020 and 2021 due to the COVID-19 pandemic.

Table of winning boats (1887–2023) Sixteen boats have been head of the river.

N.B.: Prior to 1946 were two separate rowing clubs: 1st Trinity and 3rd Trinity, hence both separate and combined titles.

Anglia Ruskin, Christ's, Clare Hall, Corpus Christi, Darwin, Girton, Homerton, Hughes Hall, King's, Magdalene, Peterhouse, Robinson, St. Catharine's, Selwyn, Sidney Sussex, St Edmund's, Wolfson, Addenbrooke's and the Veterinary School are the regular entrants never to have finished Head of the River for either the men's or women's events.

Blades, Super-Blades, Technical Blades, and Spoons

Four boat 'awards' are informally/formally recognised by the individual college boat clubs that take part in the Cambridge May Bumps, these accolades are awarded as follows: