Circa 21 Dinner Playhouse, Formerly known as The fort Armstrong theater, is an historic building located in downtown Rock Island, Illinois, United States. It opened in 1920 and it was individually listed on the National Register of Historic Places in 1980. In 2020 it was included as a contributing property in the Downtown Rock Island Historic District. It was commonly referred to as the Fort Theater. The theater was named for Fort Armstrong, a fortification that sat in the middle of the Mississippi River near the present location of the Rock Island Arsenal. Its Waitstaff, The Bootleggers, are 1 of just 2 performing Waitstaffs in the USA