Wheelchair users have done some crazy things over the years — think Rick Hansen’s round-the-world push or Mark Wellman’s climb of El Cap — but an expedition currently underway is likely to wind up near the top of the list. André Kajlich, who uses a manual wheelchair due to double above-the-knee amputations, has partnered with two other disabled adventurers to trek from the lowest point to the highest summit on every continent.

First up on the expedition, which they’re calling Lowest Highest, is South America. The team started at Laguna del Carbon, located 334 feet below sea level near the southern end of Argentina. They set off cycling with a minimal support crew, covering just under 1,600 miles to Mendoza in 12 days —an average of around 130 miles a day — while facing harsh winds and huge distances between any civilization. Kajlich uses a kneeling handcycle. His teammates, Mohamed Lahna, who rides with one leg due to a congenital condition, and Lucas Onan, who has an underdeveloped arm due to arthrogryposis, both use traditional bicycles.

All are veterans of ultra-endurance racing. Onan has completed the brutal Leadville 100-mile mountain bike and trail running races. Lahna won a Paralympic triathalon bronze at Rio 2016 and competed in the Marathon des Sables, a six-day running race across the Sahara. Kajlich is an Ironman World Champion, the only wheelchair athlete to finish an Ultraman triathalon (double the distances of an Ironman) and the first handcyclist to solo the infamous Race Across America.

From Mendoza, the team rode an old gravel road up the Andes mountains to the base of Aconcagua, where Kajlich traded his handcycle for a custom-built wheelchair that looks similar to a racing chair, but with knobby off-road tires. He pushes the chair wherever possible and then gets out and uses his arms and a swinging, scooting motion of his torso to climb the rougher terrain. Lahna, who uses a prosthetic to walk, and Onan have been doing the bulk of the work moving their equipment up the mountain, including pulling Kajlich’s chair up the sections on which he’s not able to push it.

The team has been making their way steadily up the mountain and acclimatizing to the altitude. They were planning to be pushing on to a higher camp at over 16,500 feet today. To watch as they reach the snow and prepare to make their final push up Aconcagua, follow them on Instagram @lowesthighest, where they have posted regular videos and updates. For more information on their project, which is helping to raise money for the Challenged Athletes Foundation, visit their webpage at lowesthighest.com.