SSME

When Stennis had an on-site visitor center, they displayed a Space Shuttle Main Engine (SSME) on its dolly near the entrance to the Visitor Center (Google Maps link to former location).

Unfortunately, this engine was not transferred to INFINITY Science Center with the F-1 and H-1 rocket engines. Rather, it was taken off of its dolly, rotated to a vertical orientation, and put on display in front of the Roy S. Estess Building, the main Stennis administration building (Google Maps link to current location).