Located along the Chao Phraya River in the area of Samphao Lom, Phra Nakhon Si Ayutthaya, this is the first Roman Catholic church in Thailand. Originally built during the Ayutthaya period, the current structure was completed in 1883. The church showcases a stunning Romanesque Revival architectural style, highlighted by a prominent bell tower at its center. The building features a mustard-yellow exterior complemented by white stucco patterns around the window arches. Inside, the decor is simple yet elegant, with stained-glass windows adding a touch of color. The altar is crowned with a striking dome, making it a focal point of beauty. During major festivals, the church is adorned with beautiful decorative lights, creating a mesmerizing sight.