Watapsorn Sawan Varavihara is a third-class royal temple, classified as a varavihara. Originally named Wat Moo, it is an ancient temple built during the Ayutthaya period. According to legend, it was established by Chao U, on land that was previously used for pig farming. Once it was completed, many pigs roamed around, leading the locals to call it Wat Moo. Later, during the reign of King Rama III, the temple was renovated and re-named Watapsorn Sawan. The king also donated the Buddha statue known as Phra Buddha Chan Samor, or "Luang Por Samor," to be the principal Buddha image housed within the ubosot. The Phra Buddha Chan Samor statue features a Chinese style, with the left hand holding a fruit that resembles a mangrove apple. This statue is renowned for its stunning beauty and is deeply revered by the people of Luang Prabang and Vientiane, as it is an ancient statue that originally came from Vientiane, where it was enshrined at the Phra Sri Rattana Satsadaram Temple. After the restoration of Watapsorn Sawan, Luang Por Chan Samor was enshrined at this temple, where it remains to this day. The structure of the ubosot and vihara remains authentic to its original Chinese architectural style, imitating the Royal Temple of the Crown Prince. Inside the ubosot, there are 28 principal Buddha images, all cast in the Mara Victory posture, which are identical in size and appearance, placed side by side atop a pedestal. Each of these statues has an inscription on its base, including names like Phra Tanna Khan, Phra Metha Khan, Phra Sorana Khan, Phra Tipha Khan, Phra Khondhanya, Phra Mangala, Phra Sumana, and Phra Kodam among others. Additionally, there is a Tripitaka Hall which showcases art from the Ayutthaya period, open daily for tourists and interested visitors to admire its classic beauty. The temple is located in the Pak Khlong Phasi Charoen area of Phasi Charoen, Bangkok, and can be accessed via a boat ride along the Bang Kook Yai canal. Visitors can explore the temple daily, free of charge, from 7:30 AM to 5:30 PM.