While many Czechs are enjoying their summer holidays taking it easy in the countryside or lazing on the beach abroad, a few hardy souls will soon be facing one of the ultimate sporting challenges - swimming La Manche, the English Channel.
Channel swims are attempted only in late July, August and September, when conditions are most favourable, but 21 miles (32 km) in water temperatures of 15 to 18 degrees Celsius is always an extremely tough challenge by any standards.
Planning to rise to that challenge over the next week or so - when and if they set off depending on the weather - are three Czechs: professional swimmer Yvetta Hlavacova, TV sports presenter Stanislav Bartusek and Richard Haan, who is an opera singer.
Yvetta Hlavacova doesn't just want to swim the Channel - she's aiming to set a new world record, by beating the current best time of 7 hours and 17 minutes, achieved by American Chad Hundeby in 1994. (The current Czech La Manche record is 9 hours 45 minutes, and was set by 18-year-old David Cech last year)
Hlavacova already has one record: she is listed in the Guinness Book of Records as having the longest legs in the world - 1 m 26 cm. She is also known for her uncompromising personality, publicly falling out with Czech swimming's governing body and appearing in magazines like Playboy and Penthouse.
In interviews Yvetta Hlavacova has been distancing herself from "amateur" Channel swimmers. This year two such Czech enthusiasts are also facing the ultimate long-distance swimming challenge.
Richard Haan, who is 55, is an opera soloist with the National Theatre in Brno. He has already made three attempts to swim La Manche, but on every occasion has been thwarted by bad weather.
Stanislav Bartusek, by contrast, is about to make his first attempt. Mr Bartusek is a presenter on Czech Television's sports news roundup Branky Body Vteriny, and says he wants to experience himself one of the events he has reported on. He has already completed the tough Ironman triathlon in Hawaii.
If the three make it from near England's Dover to the coast of France (which is the usual direction) they will join eight other Czechs who have managed to complete the Channel swim. The first was Frantisek Venclovsky, who swam from France to England in 1971, in a time of 15 hours 26 minutes. Four years later he went the other way, in a time of 13 hours 42 minutes.
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