Natural trials in Hin Nam Nor

Hin NamNo National Protected Area:

As its name suggests, Hin Nam No (thorny rock sprouts) is an area of jagged limestone karst landscape where the Central Indochina Limestone belt meets the Annamite mountain chain. The Hin Nam No National Protected Area lies in Boualapha District, Khammouane Province. Roughly 170km east of Thak-hek and covers an area of 82,000 ha. For most of the Hin Nam No, the habitat is characterized by vertical limestone cliffs, deep jungle gorges and a mosaic of caves and a number of wa-terfalls.



The rugged limestone coun-try has served as a refuge for several key species of primates, in particular,the endangered black langur (Trachipithecus laotum ebe-nus) and red-shanked douc langur (Pygathrixnemaeus). Other primates are present such as southern white-cheeked crested gibbon, and multiple species of macaque making this area, a priority primate protec-tion site. Further notable species contributing to the conserva-tion value of the area are four species of hornbill birds; among these, the great hornbill and the wreathed hornbill. Another bird, the sooty babbler (Stachyris herberti) is of interest to bird specialists as it inhabits only the Indochinese limestone land-scapes. Traditionally, villagers surrounding the protected area have hunted some of these animals but are now protecting wildlife and invite you to visit to experience the habitats, detect signs of these rare creatures and even see and hear the ani-mals themselves.


Must See Hin Nam No Sites:

  • Tham Nam Ork Cave

The resurgence of the Houay Hok stream. This large chamber is kept clean by seasonal inundation. The cave is reached by a 6km walk up stream from Ban Thongxam village. Otter tracks are often seen at the mouth of this cave, and a strange boulder ceiling can be investigated inside the cave. Keep quiet as you walk to this cave because you may be fortunate enough to encounter a family of black langurs either morning or evening high on a cliff-face overlooking the walking track. 

  • Tham Nok Aen Cave

The Houay Hok stream has cut a path through a limestone outcrop for about 60m. In this tunnel there is a beach for most of the way through and a constant flow of water at a depth of about 1.5m in the stream allows for swimming through the cave for those willing to face the cold and dark. Bats and swallows nest in this cave as indicated by the name “nok aen” (swallow). There are passages on the left hand side. One large cavern is lit by a sky-window where villagers say that this cave was inhabited by about 3000 North Vietnamese soldiers during the war. There is evidence of this occupation from the tin cans, and even a tooth-brush from the war-time era. Please preserve the historical value of this cave by not taking souvenirs.

  • Tham Pak Tham

This cave is the third tunnel that the Houay Hok cuts through. The mouth of the cave is located 2.7km upstream from Ban Thongxam village. It’s not known how deep the pool at the mouth of the cave is.

  • Tad Songsou 

A 20m waterfall with a deep pool at it’s base located 2.2km from Ban Nongboua. During the dry season there is usually still some water flow and is suitable for a refreshing swim after a guided walk from the village.

  • Pha Koud Macaques

Assamese macaques live only about 800m south of Ban Nongseng. These primates live in caves on Pha Koud cliff. It is unknown how they get their water ; perhaps deep in a cave. They do come down to the foot of the cliff to eat the fresh vegetative shoots. Paying a village guide to take you to see them early in the morn-ing or in the evening provides further incen-tives for conserving the remaining forest at the base of the cliffs.



Trekking Itineraries: 

Ban Thongxam Village:

1. Houay Hok Long Trail. This one day trek generally follows the stream and over a sandstone ridge, to the resurgence cave of Houay Hok stream (Nam Ork Cave). Look out for black langurs on the cliffs overlooking the path. After eat-ing lunch resume downstream to walk through Tham Nok Aen cave tunnel, then further downstream to the Tham Pak Tham cave, then back to Ban Thongxam (total length 12km, duration 7.5 hours)

2. Houay Hok Short Trail. This trek follows Houay Hok stream up to Tham Nok Aen tunnel, then further downstream to the Tham Pak Tham then back to Ban Thongxam (total length 6.5km, duration 3.5 hours).

Ban Nongboua Village:

Tad Songsou waterfall. This 2.2km walk or tractor ride takes you to a cool waterfall swimming pool at the base of Phou Cheuang Mountain.

Operating months: Dry season Only

Ban Thongxam treks are closed between June and October. Due to road conditions and stream volume. Year Round Short treks from Ban Nongboua (Tad Songsou waterfall) and Ban Nongseng (Macaque spotting at Pha Koud), may still be arranged in the wet season.


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Contact: Provincial Office of Natural Resources and Environment of Khammouane Province
Forest Resource Management Section
Anouvong Road, Laoh Phoxai Village, Thakhek District, Khammouane Province
Tel/Fax: +856 – 51 – 213 344