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The first world record in the men's 1500 metres freestyle in a long course (50 metres) swimming pool was recognised by the International Swimming Federation (FINA) in 1908. In short course (25 metres) pools, the world's governing body recognizes world records since March 3, 1991.
Video World record progression 1500 metres freestyle
Men
Long course
Short course
Maps World record progression 1500 metres freestyle
Women
Long course
Short course
src: upload.wikimedia.org
References
Source of the article : Wikipedia