Longest continuous swim in a counter-current pool (female)

The longest continuous swim in a counter-current pool by a female (and also overall) is 31 hours 7 minutes, swam by Mayra Santos (Brazil) in Caniço, Madeira, Portugal, on 5-6 November 2020. She started swimming at 10 a.m. on 5 November and ended at 4.07 p.m. the following day. The record was verified by the World Open Water Swimming Association (WOWSA).

Mayra, who moved from Brazil to the Portuguese island of Madeira more than a decade ago, took on this gruelling challenge to raise funds for the cancer charity Association of Parents and Friends of Children with Cancer (ACREDITAR).

The male record is held by Pablo Fernández Álvarez (Spain), who swam for 25 hours in an "Endless Pool" in Madrid, Spain, on 6-7 May 2020.

Over six years, this record has been extended from 16 hours (by Australian Chloë McCardel in Feb 2014) to Mayra's time of over 31 hours.