The Concorde has been there when they were flying, and most of the big military cargo planes have been there. I think one of the big Anatov's too.
The interweb says runway 18/36 in 8002 ft long x 150 ft wide.
Oshkosh Runway 18/36 is 8002' long x 150' wide but is only rated for 130 klb for double tandem and 65 klb for double wheels. My quick math says that the A380 operating weight should be less than 605,000 pounds (4 double tandem main gear and 1 double wheel nose gear) to use that runway. Runway 9/27 has a much higher capacity of 865,000 pounds but is only 6168' long x 150' wide.
In 2003, the Airbus A300-600ST (known as the "Beluga") made an appearance in honor of the 100th anniversary of the Wright Brothers' first flight. This huge transport looks like a shrimp next to the A380.