It was the world's first passenger submarine, built for Expo64, the 1964 Swiss national exhibition in Lausanne.
[1] It was built at the Giovanola fabrication plant in Monthey and the first immersion took place in Le Bouveret on 27 February 1964.
The Auguste Piccard achieved 1,100 dives in Lake Geneva with 33,000 visitors in 1964 and 1965, to a depth of approximately 150 metres.
[2] From 1969 to 1984, it achieved scientific and industrial observation dives in the Gulf of Mexico.
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