Built in 1691, the Father Miguel O'Reilly House is not only the second oldest structure in St. Augustine (the Castillo de San Marcos being the first), but also one of the oldest buildings in the United States. While recognized now as a symbol of Florida's long connection to Catholicism, the house did not take on that status until 1785. In that year, the Irish priest Father Miguel O'Reilly purchased the house and converted it into a Catholic parish rectory and made sure that it would continue to serve as a center of education and religion for years to come.

Today, the house O'Reilly House Museum focuses on three main themes. The first is the story of the house, the second is St. Augustine's Catholic tradition (which began when the area was first settled by the Spanish in 1565), and third are the Sisters of St. Joseph who have been the guardians of the O’Reilly House and educators in St. Augustine since their arrival in 1866. A visit to the O'Reilly House Museum allows you to admire its beautiful architecture, and immerse yourself in St. Augustine's proud and antiquated history.