Ximenez-Fatio House Museum is one of the best-preserved and most authentic Second Spanish Period (1783-1821) residential buildings in St. Augustine, Florida. In 1973, it was added to the National Register of Historic Places. It was designated a in 2012. The museum complex sits just south of the city's central Plaza de la ConstituciĆ³n at 20 Aviles Street (formerly Hospital Street), the oldest archaeologically documented street in the United States. It is located at the center of Old Town, the city's oldest continuously occupied community.