Boac Cathedral

Boac Cathedral, formally the Immaculate Conception Cathedral Parish, is a historic fortress church atop a hill in Mataas na Bayan, Boac, Marinduque, Philippines. Built between 1792 and 1795 by Franciscan missionaries, it served as both place of worship and defensive stronghold against pirate raids. As the seat of the Diocese of Boac, it is notable for its thick coral-stone walls, bastions, and role as the spiritual center of the island province.

Visitors can expect a hilltop fortress-church overlooking the town of Boac and the Boac River valley. The exterior features thick coral-stone walls, buttresses and bastions typical of Spanish colonial earthquake Baroque and fortress architecture. Inside is a nave with religious images, altars dedicated to the Immaculate Conception, stained glass and historic artifacts. The churchyard and perimeter offer panoramic views of Boac town, and the site is active for daily Mass and religious observances.

Constructed between 1792 and 1795 under Franciscan missionaries, Boac Cathedral was built as a fortress church using coral stone, lime and bricks to protect residents from Moro pirate raids. Its thick walls and bastions served as a refuge for the townspeople. It became the cathedral when the Diocese of Boac was established in 1978, and is recognized as an important cultural property for its Spanish colonial ecclesiastical and military architecture.

The cathedral is the spiritual center of Marinduque as the seat of the Diocese of Boac and is dedicated to the Immaculate Conception, the patroness of the province. It plays a central role in local religious life, including regular liturgical celebrations and Holy Week observances associated with the Moriones Festival, a major cultural and religious tradition of the island.