The San Matias Parish Church (Iglesia Parroquial de San Matías), commonly known as Tumauini Church, is located in Tumauini, Isabela. The church, known for its brick Baroque-style architecture, was declared a National Cultural Treasure by the National Museum of the Philippines in 1989.
The church building is made entirely of ornately-designed red bricks in its façade and its interior walls. A closer look at the brick façade shows numbers and dates for the correct sequence of the bricks. The façade is flanked by two pseudo-Corinthian columns and niches, one located above the entrance and the two remaining larger niches on each side of the columns. The church's circular pediment is unique relative to all other churches built during the Spanish Era.
Together with the churches of Boljoon, Guiuan, Loboc and Lazi, the Tumauini Church has been considered for the UNESCO World Heritage Tentative List since 2006 under the collective group of Baroque Churches of the Philippines (Extension).