The Corydon Historic District is a national historic district located in Corydon, Indiana, United States. The town of Corydon is also known as Indiana's First State Capital and as Historic Corydon. The district was added to the National Register of Historic Places in 1973, but the listing was amended in 1988 to expand the district's geographical boundaries and include additional sites. The district includes numerous historical structures, most notably the Old Capitol, the Old Treasury Building, Governor Hendricks' Headquarters, the Constitution Elm Memorial, the Posey House, the Kintner-McGrain House, and The Kintner House Inn, as well as other residential and commercial sites.

Corydon is a town in Harrison Township, Harrison County, Indiana. Located north of the Ohio River in the extreme southern part of the U.S. state of Indiana, it is the seat of government for Harrison County. Corydon was founded in 1808 and served as the capital of the Indiana Territory from 1813 to 1816. It was the site of Indiana's first constitutional convention, which was held June 10–29, 1816. Forty-three delegates convened to consider statehood for Indiana and drafted its first state constitution. Under Article XI, Section 11, of the Indiana 1816 constitution, Corydon was designated as the capital of the state, which it remained until 1825, when the seat of state government was moved to Indianapolis. In 1863, during the American Civil War, Corydon was the site of the Battle of Corydon, the only official pitched battle waged in Indiana during the war. More recently, the town's numerous historic sites have helped it become a tourist destination. A portion of its downtown area is listed in the National Register of Historic Places as the Corydon Historic District. As of the 2010 census, Corydon had a population of 3,122.