The historic Operations and Checkout Building at Kennedy Space Center has been renamed the Neil Armstrong Operations and Checkout Building.A special ceremony was held Monday morning to rename the building and mark 45 years since Armstrong first walked on the moon on July 20, 1969.The astronauts spent a great deal of time in the Operations and Checkout Building.Historic film shows Apollo 11 Command Module Pilot Mike Collins perfecting his craft there by training in the simulator for the critical undocking and docking maneuvers in the moon's orbit.In other areas of the cavernous building, workers swarmed over the Lunar Excursion Module -- the actual craft that would set down on the moon.It was where Armstrong practiced how to climb out after the moon landing.The astronauts even lived in the building while they trained.Armstrong's crewmates, Collins and Buzz Aldrin, were in attendance for the renaming of the building for Armstrong, who died two years ago.Top video: Golfer, 5, already has hole-in-one"I think we all remember Neil's one small step. But that doesn't really explain the man. Sure, he flew model airplanes, but he also built a wind tunnel. How many kids do that?" said Collins."Having Neil after Apollo 8, specifically, when questioned, asked if he wanted me to go with him, and he said yes, and I will be ever, ever grateful," said Aldrin.50 photos: History of the Kennedy Space Center