The Museum of Westward Expansion, a part of the Jefferson National Expansion Memorial National Park, is located below the Gateway Arch. And by "below" we mean "underground"! The museum is the size of a football field and it is all under the Arch grounds. It features artifacts from the Lewis and Clark Expedition, letters and documents about the Louisiana Purchase, exhibits on the native Americans that lived in the Mississippi River Valley, as well as photos and a documentary movie on how the Arch was built. Special exhibits and events change seasonally.
Visits to the museum are free to the public. Regular operating hours for the Museum are 9am - 6pm, daily. During the summer months, Memorial Day through Labor Day, the Museum is open 8am - 10pm.
The Museum of Westward Expansion
located below the Arch
St. Louis, MO 63102