One control was hidden behind an aircraft. Another could only be reached by passing through a helicopter. And for those who chose the right route through Aeroseum's underground hangars, long tunnels, staircases and unexpected route choices awaited.

When the O-Ringen Indoor race took place at Aeroseum, nearly 1,000 orienteers experienced one of the week's most unusual competition arenas – 30 metres below ground inside a former military aircraft hangar.

For Aeroseum, it was the first time hosting an orienteering event.

"It has been a fantastic experience to be part of O-Ringen and to welcome so many orienteers to our museum. I didn't even know what an indoor orienteering race was until I met you and Alfred, who designed the courses," says Aeroseum CEO Tina Dejby.

Throughout the day, the vast underground caverns filled with runners of all ages. Courses were available for every ability level, from very easy beginner courses to a challenging course with 16 controls for the most experienced competitors.

For course planner Alfred Johansson, the challenge was to make full use of the unique building.

"I always start by creating all the out-of-bounds areas and trying to design long, demanding legs. Then I place controls that look close together on the map, even though runners actually have to take a long way around."

Unlike forest orienteering, indoor orienteering is less about finding the fastest way through the terrain and more about navigating between different floors, corridors and restricted areas.

"Every staircase and every change in level became an opportunity to make the course a little more challenging," says Alfred Johansson.

One of the highlights of the race was the famous Climbing Viggen, where competitors could actually pass through the iconic Swedish fighter aircraft.

"You enter through the engine compartment at the rear and come down into the cockpit from above. We also routed the course through a helicopter, which many runners really enjoyed."

For Tina Dejby, meeting the orienteering community became just as memorable as the event itself.

"What I'll remember most is the joy, the people of all ages, and the positive energy the orienteers brought with them."

For a few hours, the former military hangar was transformed from a place once built to protect fighter aircraft into an arena filled with orienteers. By the end of the day, nearly 1,000 participants had navigated their way through tunnels, staircases and aircraft, creating a memorable new chapter in Aeroseum's history.

Facts: Indoor at Aeroseum

• The Indoor race took place at Aeroseum in Säve, just outside Gothenburg.
• Nearly 1,000 competitors took part, close to the event's participation limit.
• Courses were available for all ability levels, from very easy to advanced.
• The most difficult course featured 16 controls.
• Competitors navigated through underground caverns, tunnels and exhibitions featuring aircraft and helicopters.

Facts: About Aeroseum

• Aeroseum is an aviation museum and experience centre housed in a former military underground aircraft hangar.
• The hangar was completed in 1955, covers approximately 22,000 square metres, and lies about 30 metres below ground.
• The museum displays a large collection of military and civilian aircraft and helicopters.
• Visitors can climb aboard several aircraft and experience their cockpits and cabins up close.
• The facility also features flight simulators, exhibitions and interactive experiences focusing on Swedish aviation history.

Here are more pictures from the competition: https://mediebank.tt.se/p/svenskorientering/album/119735 External link.