The National Historic Landmarks in Indiana represent Indiana's history from the Native American era to its early European settlers and motor racing. There are 40 National Historic Landmarks (NHLs) in the state, which are located in 22 of its 92 counties. They illustrate the state's industrial and architectural heritage, as well as battles, circuses, education, and several other topics. One of the NHLs in the state has military significance, fourteen are significant examples of different architectural styles, nine are associated with significant historical figures, and one is an archaeological site.