Iran President Hassan Rouhani has congratulated Azim Gheychisaz after he became the first Iranian who climbed the all 14 of the world’s highest peaks.

Gheychisaz climbed the peak of Mount Lhotse on May 18 and joined the eight-thousanders club.

“To climb all 14 of the world’s highest peaks is a great honor,” Rouhani wrote on his Twitter account.

The eight-thousanders are the 14 independent mountains on Earth that are more than 8,000 meters (26,247 ft) high above sea level. All eight-thousanders are located in the Himalayan and Karakoram mountain ranges in Asia. Their summits are in the death zone.

Gheychisaz, 37, has done all of those ascents without supplementary oxygen, without Hi-porters.

Only 36 other climbers in the world have documented their climbs to all 14 of the world’s highest peaks. The first mountaineer to make such an achievement was Reinhold Messner, in 1986.