Wat Si Uthumphon

Luang Pho Choi Chanthasuwanno was born on 8 April 1913 at Phrong Song Nang, Thap Than, Uthai Thani, and ordained at Wat Don Wai on 7 May 1933. Nakhon Sawan Rajabhat University's temple database says building began in 1932; in 1942 Wang Duea villagers invited Luang Pho Choi to lead it, the date usually given as its founding; the old ordination hall was built in 1950, and in 1951 it was officially recognised and granted its boundary. He set up dharma and Pali schools in 1947 and 1952 and a vipassana centre in 1955, and became famous for ritual knives (mit mo), earning the title 'god of Pak Nam Pho'.

In 1994 Princess Sirindhorn opened the temple's commemorative library. In 2003 Luang Pho Choi gave 589 rai of adjoining land to the princess for the Chaipattana Foundation. He died on 16 April 2007, aged 94 after 74 rains; his body did not decay and lies in a glass coffin in the mondop. Every 16 April is his memorial day.

The 'floating' ordination hall has two storeys raised on about 100 pillars, with columns, walls and ceilings clad in five-colour Benjarong porcelain, tiles and silver and gold spoons and bowls set in white stucco. The ground floor is entered through the open mouth of a stucco Hanuman flanked by giants, and inside are blue-ground murals and low stucco reliefs. On 7 February 2022 Princess Sirindhorn raised the hall's roof finial and planted a Champi Sirindhorn tree at the library-mondop.

A hall behind the ordination hall holds the Thep Sattrawut ritual knife: 9 m long, 83 cm wide and 3,000 kg, with a 5 m steel blade and a 4 m takhian-wood handle, made on 26 April 2015 as engraved on the blade, with one of Luang Pho Choi's robes sealed inside; the 'world's largest' claim is unverified. There are also four teak halls, jade Buddhas, wax figures of revered monks, a three-headed Erawan elephant and the Mae Si Mani Thong takhian tree, popular with lottery players. On 10 November 2024 a royal kathin was presented through the Chaipattana Foundation. The current abbot is Luang Pho Somsak Panyatharo.

It is open 08:00–17:00 and free; cover shoulders and knees and remove shoes indoors. There is no public transport, so drive or take a taxi toward Nong Krot. Parts are still under construction, and sensitive visitors should know a monk's body is on display. November–February is the most comfortable, and the interiors work in any month.