Apollo 16 was the fifth mission in which humans walked on the lunar surface and returned to Earth. On 21 April 1972 two astronauts (Apollo 16 Commander John W. Young and LM pilot Charles M. Duke, Jr.) landed in the Descartes region of the Moon in the Lunar Module (LM) while the Command and Service Module (CSM) (with CM pilot Thomas K. Mattingly, II) continued in lunar orbit. During their stay on the Moon, the astronauts set up scientific experiments, took photographs, and collected lunar samples. The LM took off from the Moon on 24 April and the astronauts returned to Earth on 27 April.
References
http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1972-031A