Tumacácori National Historical Park is located in the upper Santa Cruz River Valley in Santa Cruz County, southern Arizona. The park consists of 360 acres (1.5 km2) in three separate units. The park protects the ruins of three Spanish mission communities, two of which are National Historic Landmark sites. It also contains the landmark 1937 Tumacácori Museum building, also a National Historic Landmark.
Tumacácori Museum was built in 1937 within what was then Tumacácori National Monument and is now Tumacácori National Historical Park. Designed by Scofield Delong, it contains interpretative displays relating to three historic missions preserved within the park, and includes artwork created by artist Herbert A. Collins.
The museum building, a fine example of Mission Revival style architecture, with Spanish Colonial Revival details, was declared a National Historic Landmark in 1987.
The Tumacácori missions complex was originally protected as Tumacácori National Monument, in 1908 by President Theodore Roosevelt. It was listed on the National Register of Historic Places on October 15, 1966. In 1990 the national monument was redesignated a National Historical Park. The Guevavi and Calabazas mission units were added to the Tumacácori missions complex unit, within the new Tumacácori National Historical Park.
The site was on the route of the 1775-1776 Juan Bautista de Anza Expedition from New Spain to Alta California, the first Spanish overland expedition to claimed but un-colonized upper Las Californias territory. A 4.5 miles (7.2 km) segment of the Juan Bautista de Anza National Historic Trail lies along the Santa Cruz River between Tumacácori National Historical Park and Tubac Presidio State Historic Park.