The EAA is the World's Largest Organization of Aviation Innovation, and their Museum pays tribute to the breakthroughs in Air Travel. More than 200 unique and unusual vintage, restored, and replica Aircraft are on display. Some featured exhibits include full-sized replicas of the Spirit of St. Louis, Voyager, and Spaceship One, and an entire wing of restored WWII aircraft. There are also flight simulators, and many kids activities.
If you go:
The EAA Airventure is known as 'The Worlds Greatest Aviation Celebration' and is held for 1 week each year in July/August. The event brings in thousands of aviation fans from around the world, and turns Oshkosh into the busiest airport in the world during that week!
Links:

3000 Poberezny Road
Oshkosh, Wisconsin 54903 USA
museum@eaa.org
Mailing address:
PO Box 3086
Oshkosh, WI 54903 USA
Phone Numbers:
General Info
+1 (920) 426-4818
+1 (920) 426-4818
Museum Store
+1 (920) 426-6108
+1 (920) 426-6108
Pioneer Airport
+1 (920) 426-4867
+1 (920) 426-4867
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