Acali

The Acali expedition (or Acali experiment ) was a 1973 social experiment that aimed to investigate interpersonal relationships in conditions of limited space and social isolation. The experiment was conceived by Mexican anthropologist Santiago Genovés, who had previously been a crew member of Thor Heyerdahl's Ra expedition. The participants showed a restraint towards aggression, which frustrated Genovés and led him to start to try to create conflict, and at one point he took command of the float. Despite these attempts, the group remained peaceful.

The raft had a complement of eleven people: five men and six women. It left Las Palmas, Spain, on 12 May 1973 and took 101 days to drift across the Atlantic Ocean and reach Cozumel, Mexico, with a single stopover in Barbados. Frequently dubbed the "Sex Raft" by the media, it was the subject of a 2018 documentary film The Raft, by Marcus Lindeen.

The raft
The name of the raft, Acali, comes from the Nahuatl language and means "the house on the water".

The raft was built specifically for the experiment. It had a steel hull and dimensions of 12 by 7 metres. The cabin measured 4 x 4 metres in area. It was designed by José Antonio Mandri and Colin Mudie, and it was built in Newcastle upon Tyne, UK.