Nan province - northern Thailand
Mani Phruek caves (Mani Phruk)
There are several caves in the area of Mani Phruek (Mani Phruk), close to an hill tribe village. The most famous one, Tham Pha Phueng, is one of the most spectacular cave entrances, and the deepest cave of Thailand.
Tham Pha Phueng ถ้ำผาผึ้ง
The cave is close to Ban Mani Phruek 1 H'Mong village, and can be visited without being accompanied by a guide. The cave entrance is reached by a 5 minutes walk.
For the other caves, you will need a local guide from the nearby Department of Forestry, as they request a trek in the forest.
Tham Champi ถ้ำจําปี
This cave is 4.5 km. north-west of Ban Mani Phruek 1 and 400 metres lower in altitude. There is a track from the village that can take you to about 1 km. from the cave. Recommend getting a guide. The cave is 400 metres long and well decorated, though it does also have a lot of bats.
Tham Ho Ying ถ้ำหอหญิง - Tham Ho Chai ถ้ำหอชาย
These caves are on Phu Hua Lan mountain, up the hill from Tham Champi. There are still landmines on Phu Hua Lan (there are warning signs) so stick to the footpaths and, preferably, have a local guide. Both caves are short (Tham Ho Ying is 100 metres long and Tham Ho Chai 30 metres long), but have some formations.
Tham Pha Daeng ถ้ำผาแดง
This is the well-known Communist base camp cave. It is about 9 km. north of Ban Mani Phruek 1 and can be accessed via the good track that goes along the ridge to the north-east of the village. As there are no signs once past the village a local guide is recommended.
Tham Phu Hua Lan ถ้ำภูหัวล้าน
Tham Nam Dan (Tham Nam Mudt) ถ้ำนํ้าดั้น (ถ้ำนํ้ามด)
Tham Nam Tok Nam Poen ถ้ำน้ำตกน้ำปิน
Tham Huai Poen ถ้ำห้วยปิน
Many thanks to Martin Ellis for his useful information