Cyclists from 11 countries will compete at what is considered as one of the most demanding and best organised extreme distance cycling races in Europe.

"The number of registered cyclists is on par with last year, but we are happy that some leading names from abroad and home are returning to DOS," said DOS Extreme race director Andrej Berginc.

The famous names on the list of starters include Slovenian champion Marko Baloh, who will race this year in the pairs competition with US cyclist Kerry M. Ryan, and Austria's Eduard Fuchs.

They will have to contend with nearly 14,000 metres of climbs as they make their rounds around Slovenia to the finish line back in Postojna. The first finishers are expected to require around 40 hours to complete the race.

This is the ninth time that the Race Around Slovenia has been put on the calendar of the World Cup.

It will also serve as a qualifying competition for the Race Across America, which remains the holy grail of extreme cycling competitions in the world.