This two-story adobe with balcony was built in 1838 by Jose Tiburcio Castro, a former Spanish soldier, for his son Jose Antonio Castro. It was to serve as the Judicial and Administrative Headquarters for the Northern District of Alta California, Mexico. Jose Antonio Castro became a Commandante-General in the Mexican Army during the Mexican-American War, and would eventually serve as Acting Governor of Alta California. The building is an outstanding and little-altered example of a Monterey Colonial House.
When the Patrick Breen family of nine arrived in San Juan after their arduous journey over the Serra, General Castro invited them to live in his house. In 1848 the eldest Breen son, John, took a family horse and joined in the Gold Rush. After a year he returned with $12,000 in gold dust, enough to purchase the adobe from General Castro. As Castro did not have an actual title to the building it wasn’t until 1885 that the U.S. Supreme Court validated the land patented to the Castro’s, and thus the sale was deemed valid.
At the start of the Gold Rush there had been no hotel in San Juan. The Breen’s offered their home, even while they were living there, as accommodations for travelers. It became known as The United States Tavern Inn.
Members of the Breen family owned and occupied the house from its purchase until 1933 when it became part of the California State Park System. Today the adobe may be viewed by visitors to the San Juan Bautista State Park.