On Sunday 4 April 2021, 46 year old monk Phra Ajarn Manas, on his annual pilgrimage from Nakhon Sawan province, entered Tham Phra Sai Ngam to meditate. This 3 km long cave is on the western edge of the Thung Salaeng Luang National Park, 6 km north of Noen Maprang in Phitsanulok province. While he was in the cave a heavy thunderstorm caused a seasonal sump, 400 m from the entrance, to close trapping him in the cave. As the monk was planning to spend a long time in the cave (he reportedly had some food with him) the alarm wasn’t raised until noon on Tuesday 6 April.

In February 2020 a team of twenty-two cavers, mainly from the Shepton Mallet Caving Club and Chiang Mai Rock Climbing Adventures, explored and surveyed caves in the Doi Angkhang region of Chiang Mai province. This mountainous karst region is on the border with Myanmar and the area explored included parts of the Angkhang Royal Agricultural Station, Doi Phahom Pok National Park and Pha Daeng National Park. In two weeks a total of 5.4 km of passage was mapped in 14 caves.