One of the little noted facts about the Apollo program is that three men actually went to the moon twice by virtue of having been on the lunar orbit missions of Apollo 8 or Apollo 10 and then being part of a later moon landing mission.
Jim Lovell first traveled to the moon as part of the Apollo 8 lunar orbit mission in December 1968. He had already been on two Gemini lunar orbit missions, one with his fellow Apollo 8 astronaut Frank Borman on Gemini 7 and the other with future moon walker and painter Alan Bean on Gemini 12. Apollo 8 made 10 orbits of the moon that featured real time observations of the lunar surface, the iconic Earthrise, and the reading from the Book of Genesis.
Lovell made a second trip to the moon as commander of Apollo 13 in the third mission to land on the lunar surface. But because of an accidental explosion in one of the fuel tanks of the Apollo service module, Lovell and his crew were obliged to circle around the moon and return to Earth in a free return maneuver.
The other two men who went to the moon twice flew on Apollo 10, which tested both the command/service module and the lunar module in lunar orbit in May, 1969. They were John Young and Gene Cernan. Young had flown on both Gemini 3 and Gemini and Gemini 10. Cernan had flown as part of Gemini 9. The Apollo 10 mission was considered a dress rehearsal for Apollo 11, performing all of the maneuvers for the latter mission except for the moon landing itself.
Young commanded the Apollo 16 mission in April, 1972. Young and fellow astronaut Charlie Duke landed in the Descartes Highlands and stayed for three days, performing three EVAs with the lunar rover, setting up experiments and collecting rock and soil samples.
Cernan commanded the Apollo 17 mission in December, 1972. Young and Harrison Schmitt, the only geologist to have walked on the moon, landed at Taurus-Littrow and set up experiments and collected rock and soil samples. Because Apollo 17 was the final mission to the moon, Cernan has the somewhat melancholy distinction of being the last man on the moon.