A Swiss athlete, Urban Schumacher, has won one of the most gruelling races, the gigathlon which comprised five different sports and passed through five cantons.
Schumacher, the favourite, finished the multi-discipline course in 13 hours 59 minutes and 37 seconds.
His time was half an hour faster than the American, Rod Raymond, who won the race when it was first held two years ago. Raymond did not take part this time.
More than 3,000 people took part in what is arguably Switzerland's most gruelling endurance test. An initial 48-kilometre mountain bike ride in the south-east of the country was followed by 122 kilometres of cycling from Savognin in canton Graubünden to Niederurnen in canton Glarus.
The competitors moved on to inline skates for the 28-kilometre stretch from Niederurnen to Lachen, followed by a three and a half kilometre swim from Lachen to Rapperswil before the final marathon race that took the weary athletes into the Hallenstadion in Zurich.
The competitors also had to cope with major altitude differences. A total of 459 teams, 50 couples and 226 solo athletes took part in the event, sponsored by the Elektrizitätswerk der Stadt Zurich.
swissinfo with agencies
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