May Bumps

The May Bumps (also May Races, Mays) are a set of rowing races, held annually on the River Cam in Cambridge. 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 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.

The most recent in the series was the May Bumps 2016, which ran from 8 June 2016 until 11 June 2016.

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 8 rowers and one coxswain. A total of 154 crews took part in 2014, totalling around 1390 participants. There are currently 6 divisions for men's crews (referred to as M1, M2....M6) and 4 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.

At the start, signalled by a cannon, each crew is separated by a distance of about 1½ boat lengths (approximately 30m or 90'). 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 3 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.

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 :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.

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