Apollo-Soyuz Hatch of Mutual Understanding.
Stafford Air and Space Museum
Weatherford, Oklahoma
Weatherford is the hometown of Thomas P. Stafford, one of a handful of astronauts who flew to the moon before Apollo 11. He also commanded the USA side of the Apollo-Soyuz mission, and one of his museum's displays is the hatch through which he and the Russian commander exchanged handshakes -- a big deal for the Cold War year of 1975. The museum exhibits a full-size indoor Titan II rocket, used to launch Gemini space capsules and Mark VI nuclear warheads, which the museum also has.
Though Stafford never actually walked on the moon, his museum was still considered important enough to merit its own moon rock, brought back on Apollo 17.