The Baroque Church of Santa Maria, Ilocos Sur was considered masterpiece. It was listed in the UNESCO World Heritage Site. Actually, Ilocos Sur has two sites that is included in the UNESCO list, the other one is The Vigan City.
The Santa Maria Church is one of the four European church design in local construction techniques and decorations. The others were San Agustin of Manila, Santo Tomas of Miag-ao, San Agustin of Paoay, and La Asunsion of Santa Maria. Their specific characteristics include a separate bell-tower and strong buttresses to withstand the powers of earthquakes common in the region.