The 
Boat Race is a race between the rowers of 
Oxford University and 
Cambridge University along a particular stretch of the 
River Thames in 
England which takes place at the beginning of Spring-except in one year when there were two races. Only in one year was there a draw.
According to tradition, the loser has to invite the winner for a new race. 
"I can't see whose in the lead but it's either Oxford or Cambridge" -John Snagge.
Because of this event, boat race has become rhyming slang[?] for face.
There are a number of boat races around the world, some of which take place in dry rivers.
 
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