Wat Don Yai (วัดดอนใหญ่), i.e. the ‘Temple of the Large Mound’, is a Buddhist temple of the Mahanikaya (มหานิกาย) monastic order located in Lam Luk Ka (ลำลูกกา) Subdistrict, Lam Luk Ka District, Pathum Thani (ปทุมธานี) Province, Thailand. Established in 1910 (B.E. 2453), the temple was founded on farmland donated by Luang Yotha Nareuban (หลวงโยธานฤบาล) and his wife Nang Sa-at (นางสะอาด), with additional land later offered by Nang Pheum (นางเพิ่ม). Because of its location along the canal network, local residents referred to it as Wat Klang Khlong Paet (วัดกลางคลองแปด). The temple received its royal ordination boundary, Wisungkhamsima (วิสุงคามสีมา), on 4 August 1922 (B.E. 2465). A distinctive feature of the temple is its Silver Ubosot (อุโบสถ), an ordination hall built in a four-gabled chaturamuk (จัตุรมุข) style. In 2026, the chapel was not yet completed, and the look nimit (ลูกนิมิต)—large, round, cannonball-like boundary stones used to demarcate the sacred limits of the consecrated ordination hall—were displayed around the bot (โบสถ์). Each stone stood beside a small mondop (มณฑป)-like structure (fig.) intended to house the bai sema (ใบเสมา) boundary markers. Inside the ubosot, alongside several wax effigies of revered monks from the past, stands the large white Phra prathaan (พระประธาน), i.e. the principal Buddha statue, named Somdet Phra Suwan Pathum Phutthaphotchana Woraphon (สมเด็จพระสุวรรณปทุมพุทธพจนวราภรณ์), popularly known as Luang Pho Jai Dee Mang Mee Sri Suk (หลวงพ่อใจดีมั่งมีศรีสุข). A wihaan (วิหาร) within the temple houses various revered figures, including Phra Phikanet (พระพิฆเณศ), Phra Phrom (พระพรหม), Thao Jatukham Ramathep (ท้าวจตุคามรามเทพ), Thep Thanjai (เทพทันใจ), Phra Mae Thorani (พระแม่ธรณี), Phra Siwalee (พระสีวลี), Phra Upakhut (พระอุปคุต), Phra Phuttha Chinnarat (พระพุทธชินราช), and Ai Khai (ไอ้ไข่). The grounds also contain memorials to King Naresuan (นเรศวร), King Taksin(ตากสิน), and King Chulalongkorn (พระปิยมหาราช), as well as a fish pond where visitors may feed fish as a merit-making activity. Directly opposite the temple lies Phaya Naga Nature Park (อุทยานธรรมพญานาคราช), also known as Phaya Naga Nature Park of the Four Clans (อุทยานธรรมพญานาคราช 4 ตระกูล). This site features large naga sculptures, a white Buddha image in the Open the World posture, Pang Peut Lohk (ปางเปิดโลก), and a 160-metre-long walkway known as Saphaan Kaew Naak Baht (สะพานแก้วนาคบาศ). The park represents the four naga lineages, Phaya Naga See Trakoon (พญานาค 4 ตระกูล): Wiroopak (วิรูปักษ์), associated with golden scales and high status; Erapahtha (เอราปถะ), depicted with green scales and closely linked to human legends; Chapphayahputta (ฉัพพยาปุตตะ), portrayed with rainbow-coloured scales and believed to inhabit hidden realms; and Kanha Gohta-ma (กัณหาโคตะมะ), represented with dark scales. Together, Wat Don Yai and the adjacent park form a religious and cultural landscape reflecting both Theravada Buddhist worship and enduring naga traditions in Thai belief. Also known locally as Wat Klang Khlong Paet (วัดกลางคลองแปด). 回