Tham Chom Ong

Chom Ong Cave

Useful Information

Location: Near Khamu Lu village of Chom-aung Neua and Chom Ong tai villages. 45 km from Oudomxay town. Xay district, northern Laos.
Classification: SpeleologyKarst cave
Light: LightIncandescent Electric Light System
Dimension: L=13,473m
Guided tours: D=4 h.
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
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NOV-2006 start of development.
2007 education of the town people as cave guides.
JAN-2009 exploration by an international team of cavers. Surveyed length 13,473 m.
JAN-2010 exploration completed, total lenght of 16 km.
JAN-2010 opened to the public.


Tham Chom Ong (Chom Ong Cave) is currently the second longest cave of Laos ([2009]: L=13,473 m). However, according to the exploration team from the Northern Lao-European Cave Project - which is currently in the process of surveying this cave - the length will increase with future expeditions as there are still many open leads.

The Tourism Office of Xay district (Oudomxay province) has now developed Tham Chom Ong for tourism. This includes also a guesthouse in Chom Ong village. In 2007 the local government, assisted by the Deutscher Entwicklungsdienst, educated the villagers in the management of a show cave and safely guiding visitors. Toiletts, a laundry room, and drinking water supply with ceramic filters were created. The first 450 m of the cave were developed with electric light. This show cave was opened in January 2010.

The cave is also visited on four hour caving trips, which are actually not for the average tourist. The tour requires an easy one hour long walk with several shallow river crossings from Chom Ong village to the southern cave entrances and of course the way back, so the tour is actually a full day tour. Chom Ong Cave is the source of the Nam Kaang River, the tour follows the cave river upstream for 1,600 m in a dry upper level. The passage is rather big with chambers between 20 m and 35 m wide.

The cave is named after nearby Ban (village) Chom Ong. Chom On means beehive in Khmu, the traditional profession of the villagers is beekeeping. The locals call the cave Tam Chia (Bat Cave), which is not really a very good name. A lot of caves in Laos are named bat cave, so the cave was given a unique name by the researchers.