Made of mortar and coral stone, this edifice is a fine example of mid-colonization Filipino-Spanish architecture. It was built under the polo system of forced labor for a total of 53 years, started in 1830 and finished in 1883. Bato Church has withstood wars, calamities and the ravages of time to become the only remaining structure of its genre in the entire island and the second-largest church in Bicol region. In its tower still houses the legendary bell that once served as a warning device for incoming Japanese guerrillas during the Second World War. Seen from the other side of the river the old church looks majestic and imposing.  Proudly the church stands as the oldest in the province.

From http://catanduanes.gov.ph/bato-church/