Hotel Terme Millepini

Hotel Terme Millepini is a four-star hotel in Montegrotto Terme, Padua, Italy. It contains 100 rooms and is recognized for having the world's deepest pool, the Y-40, which put it in the Guinness World Records. The hotel was first built in 1997 and renovated in 2013.
Y-40 "The Deep Joy" pool first opened on 5 June 2014 and was designed by architect Emanuele Boaretto. It is 42.15 metres deep, making it the deepest pool in the world. It contains 4,300 cubic metres
of thermal water kept at a temperature of 32–34 °C . The pool features underwater caves and a suspended, transparent, underwater tunnel for guests to walk through. It includes platforms at various depths, ranging from 1.3 metres to 12 metres , before the walls of the pool narrow into a well-like funnel which plunges straight down to 40 metres . The hotel offers tickets to freedive and scuba dive. Italian freediver Umberto Pelizzari first measured the depth before the pool was open.

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