More than 90% of the population in Wanjin Village believes in Catholicism. It is a very special Catholic village. Many residents of neighboring Chishan and Jiapaolang settlements also take this as their belief. In May of the 2nd year of Tongzhi (1863), the Dominican missionary Father Guo Degang (Fernando Sainz, O.P.) built the first earthen church in Wanjin. In the 5th year of Tongzhi, the church was completely destroyed due to mob arson, without leaving any image records. In December of the 8th year of Tongzhi (1869), a solid church was built in the Chishan area (now Chishan Village and Wanjin Village of Wanluan Township). Inside the church there were three holy statues that were shipped from the Philippines, making it the oldest existing Catholic Church in Taiwan, this is Wanjin Catholic Basilica or also known as the Wanchin Basilica of the Immaculate Conception.
The construction of the Wanjin Catholic Church completed in the 9th year of Tongzhi (1870). It is a traditional European Gothic church building with a width of 57 feet, a depth of 116 feet, a height of 25 feet, and an outer wall thickness of 2 feet. In the 13th year of Tongzhi (1874), the Qing Emperor issued the "Fengzhi" approval, and the sacred stone with the words "Catholic Church" was personally sent by Shen Baozhen to the Wanjin Temple and hung at the entrance of the church. In 1984, the church was conferred the title of basilica by Pope John Paul II, making it the first church in Taiwan to receive such title. This means the first-level church in the Catholic Church that enjoys the highest charism in the church. Wanjin Catholic Church underwent multile renovations during the 11th year of Guangxu (1885) and 1960. Yet today it retains its original appearance , like a medieval castle.