Owned and occupied by the Leopoldo Carrillo family, this 1880's house was rented by the fifth Territorial Governor Fremont and his daughter in 1881. It is listed in the National Register of Historic Places. The house is open Wednesday through Saturday.

The Sosa-Carrillo-Fremont House is unique because it offers such a broad view of Tucson history and about the families that have helped shape this history. The people who owned and occupied the house played many important roles in the rapid growth of 19th century Tucson.

The Sosa-Carrillo-Fremont House is best known as the John C. Fremont House, it is ironic that John Fremont never even owned the property. John Fremont is an important name in the early history of Arizona. He was an explorer of the American West, a civil war general and in 1880 he was made the fifth governor of the Arizona territory.