What name did Apollo 11 astronauts give the site where they first landed on the Moon?

Apollo 11 astronauts named their first lunar landing site Tranquility Base.

The site was located in the southwestern Mare Tranquillitatis, or Sea of Tranquility. The lunar module Eagle touched down there on 20 July 1969, carrying Neil Armstrong and Buzz Aldrin. Armstrong announced the successful landing with the words, “Houston, Tranquility Base here. The Eagle has landed.”

The name was chosen as a reference to the Sea of Tranquility and to convey the calm after the difficult powered descent. The landing coordinates are approximately 0.67408° north latitude and 23.47297° east longitude. Apollo 11’s landing site remains marked by the descent stage and equipment left on the Moon.

Tranquility Base was not a permanent settlement or scientific station. It was the mission’s call sign for the landing site. Later Apollo missions used different site names, including Fra Mauro for Apollo 14 and Hadley–Apennine for Apollo 15.