Orienteering takes its first steps into a new era this week with a new format for the World Championships in Norway.
Athletes from 48 different nations will take part in the Championships across the three disciplines of middle, long and relay races, on the rugged terrain of the Østfold region.
It's the first time the World Orienteering Championships (WOC) has been split into two events.
This year sees the "Forest WOC", with competition in wooded areas, while next year will see the "Urban WOC" for sprint events.
Both formats would have been contested this year, but the structure has been newly streamlined.
The four days of competition begin tomorrow with the middle qualification, with the top 15 from the three heats in both the men's and women's events qualifying for the final.
The best placed competitor from a nation with no athletes in the top 15 will also reach the final, as long as their finishing time is within 100 per cent of the winner's score.
The long distance event takes place on Wednesday (August 14), with up to three competitors from each nation allowed to take part based on results from previous Championships.
The middle distance final takes place on Friday, with the relay event concluding the Championships the following day.
Østfold promises to offer plenty of challenges, with forests, hills and marshy areas on lower ground.