By Krisztina Fenyo

REVFULOP, Hungary (Reuters) - Under cloudless summer skies, thousands of competitors plunged into the balmy waters of Balaton on Saturday to swim across Central Europe's largest freshwater lake.

Despite the coronavirus pandemic, organisers said more than 10,000 people including children, pensioners and professional athletes had registered to take part in the annual lake swim - Europe's longest open-water swimming contest.

Bela Gurban, 66, who swam the 5.2-kilometre (3.2-mile) course for the 38th time this year, said nothing would deter him from taking part in the swim from Revfulop, a village on the hilly northern shore to Balatonboglar on the southern side.

"Climbing out on the other shore feels like a miracle," Gurban said, adding that his dream is to swim the stretch of water accompanied by all six of his grandchildren.

Due to measures to contain the virus, all the race participants had temperature checks before starting and were let into the water one by one at entry points to allow social distancing.

Sailing boats escorted the swimmers across the lake to the opposite shore, where crowds of people waited on the beach to greet them.

The winner, Hungarian world and European champion openwater swimmer Kristof Rasovszky, completed the distance in 57 minutes, setting a new record despite the sweltering conditions.

The water was 26 degrees Celsius (79F), with outside temperatures scaling 33C.

The oldest participant, 83-year-old Tivadar Runtag, said he had swam across the lake 14 times before. He thanked his wife for "tolerating" his hobby during their 59-year marriage.

Runtag, who recovered from cancer 24 years ago, said he swims three kilometres every good day and a bit less on "less blessed days."

"It was nice to watch those teenagers besides me, as they are energetic and want to live a healthier life," he said.

(Writing by Krisztina Than; Editing by Helen Popper)