A UNESCO World Heritage Site and one of the four Baroque Churches of the Philippines, built between 1694 and 1710 by Augustinian friars. Its massive coral stone buttresses showcase a unique Earthquake Baroque architectural style designed to withstand seismic activity. The church and its separate bell tower are masterpieces of Filipino-Hispanic architecture.
| Category | Heritage |
| Province | Ilocos Norte |
| Region | Region I - Ilocos Region |
| Coordinates | 18.05280000, 120.51690000 |