In general, FIREARMS ARE PROHIBITED at Tumacácori National Historical Park.
As of February 22, 2010, federal law allowed people who can legally possess firearms under applicable federal, state, and local laws, to legally possess firearms in national parks. However, Federal law prohibits firearms in the facilities of this park. One such facillity is the visitor center through which all visitors to the park must pass to access other areas and facilities of the park. The public entrance door to the visitor center is clearly marked with a sign indicating that firearms are prohibited.
The exception to the "firearms prohibited" law are those areas of the park that are accessible only via the Juan Bautista de Anza National Historic Trail. While those areas are governed by the new federal law allowing the possession of firearms in accordance with Arizona State law, hunting or any other use of such firearms is illegal.
It is the responsibility of visitors to understand and comply with all applicable state, local, and federal firearms laws before entering this park. As a starting point, visit the Arizona Attorney General's website.