NASA Photo ID: 81-H-174, S81-29126
Date Taken: 03/19/81

Astronaut John W. Young, commander of the two-man crew for the maiden flight of the Space Shuttle Columbia is in the suiting room at the operations and checkout building at the Kennedy Space Center (KSC). He's taking part in "pre-launch" activity during a simulation session which will include a mock countdown and simulated launch.

Source: NASA photo in my possession