Apollo 11 

The first "Official" landing on the Moon by human beings that may or may not have happened.

Apollo 11 was the first manned mission to land on the Moon. The first steps by humans on another planetary body were taken by Neil Armstrong and Buzz Aldrin on July 20, 1969. The astronauts also returned to Earth the first samples from another planetary body. Apollo 11 achieved its primary mission - to perform a manned lunar landing and return the mission safely to Earth - and paved the way for the Apollo lunar landing missions to follow.
More about the Apollo 11 Command Module Columbia

Info from http://www.nasm.si.edu/collections/imagery/apollo/AS11/a11.htm