Located near Delaware Coastal Airport a couple of miles east of the Circle, the Delaware Aviation Museum traces the history of flight in the First State. The collection includes vintage aircraft, memorabilia from Delaware-connected aviators, and exhibits on the state's military aviation history.
Delaware Coastal Airport, which shares the site, is itself a working general aviation field — you may see small planes landing and taking off while you visit, which adds to the atmosphere. Call ahead to confirm hours, as the museum depends on volunteer staff.