Tommy Caldwell and Kevin Jorgeson have climbed the Dawn Wall of El Capitan, a rock formation in Yosemite National Park, USA.
The climb is described as the most difficult climb in the world, because the face is so steep, so tall, and so smooth. It is also 914m tall – three times the height of the Auckland Sky Tower, and taller than the biggest skyscraper in the world.
The two climbers took 19 days to complete the climb and had to camp overnight on the rockface.
What is free climbing?
Free-climbers use just their hands and feet to climb a mountain, rather than using tools or pulling themselves up on ropes.
They wear rubber shoes to help their feet cling to the rock face, and climb up the rock face using their fingertips.
But the men were also attached to safety ropes to stop them from falling all the way down if they slipped.