Venture along the Mekong River between the provinces of Ubon Ratchathani and Mukdahan in I-san, Thailand’s Northeast, and step into an otherworld unlike anything in Thailand — or Southeast Asia for that matter. Great sandstone plates rear up, stone “mushrooms” thrust into the sky, massive black rocks define swirling rapids. Tall cliffs soar, their faces inscribed with arcane symbols in blood red, written by an unknown people eons ago. Only waterfalls and wildflowers soften this wild landscape.

Whereas Central and Northern Thailand are dotted with sculptures shaped by human hands, here the sculptor is the wind, water and the sun. Appropriately for its primeval setting, it is the first part of Thailand the sun visits each morning.

Four key sites — Kaeng Tana, Pha Taem, the Mekong River and Phu Pha Toeb — lie along a road that leads through a wealth of geological formations reminiscent of Mars, the Moon or a meteorite. The landscape is a fabric of infinite hues and patterns in a region that suggests a visitation from the heavens and habitation by the peoples of pre-history.

KAENG TANA NATIONAL PARK

	North of Ubon, near Khong Chiam, one enters the 80 square kilometres of Kaeng Tana National Park. Bisected by the fabled Mun River, this is a region that portends the alien landforms to come. Black rocks and broken sandstone slabs are jumbled together along the riverbanks, their solidity crafted and displaced by cosmic forces. Water has etched the sandstone plates into intricate patterns; looking down on them is like viewing earth from space. In the swirling waters, grit, propelled by the currents has, over eons, pitted and pocked the ebony stones and ground potholes into the rock surfaces, scouring depressions that lend the stones the look of meteorites.
	The surrounding landscape is harsh. The vegetation is spare, reflecting an ancient, epic standoff between tough trees and unyielding stone. Just downstream from Kaeng Tana, at Khong Chiam, the Mun flows into the mighty Mekong, its clear green waters declining to merge with the Mekong’s silt-laden stream. Instead, the two flow side by side for dozens of metres to create a two-colour river. It is a point of pride for the neighbouring villages with boatmen ferrying visitors from Ban Park La to Ban Kan Tha Kwian to witness it first-hand.
	During the monsoon season, the Mun’s surging waters submerge Kaeng Tana’s myriad mid-stream islands and, with them, the Ton Na Saeng trees that cling on tenaciously. The turbulent river bends the trees and their roots to point downstream, parallel with the Mun itself.
	Similar rapids (kaeng means rapid) are those at Kaeng Saphue at Piboon Mangsahan.
	From the towering cliffs dominated by Wat Thamkhuasawan and its blinding golden chedi, a massive seated Buddha gazes down on fishermen casting wide, round nets along water-worn sandstone terraces.

Some 400 million years ago, the Northeast was covered by an ancient ocean; a layer of seashells at Sao Chaliang attests to its marine origins. The centrepiece of the 340 -square-kilometre park is Phu Pha Kham, a tall cliff overlooking the Mekong River and Laos on its opposite bank.

The sea receded and subsequent erosion carved downwards through the soft surrounding soil to leave a 60-metre-high cliff composed primarily of limestone and sandstone. It is capped by a massive, 200-metre-long flat, slightly sloping plate.

Here, one is uncertain whether one is still on planet earth. He inhabits by turns, the Moon, Mars and meteorites. The bones of the earth are laid bare. Embossed interstices, rocks that resemble bone, deep crevices — all are testament to cataclysmic prehistoric forces. Eons of evolution lie before one, every strata like the pages of a book viewed side on.

Sit at the butte’s edge as the sun is rising above Laos. The view alone is entrancing, across a dry dipterocarp and the Mekong River that rims it. Under a full moon, the scene becomes magnificent and mysterious.

At one edge of the cliff is Kok Hin (‘Stone Enclosure’). The purpose of its circle of stacked rocks is unknown. It may be for worship — a place where supplicants gathered to greet the morning sun. Some believe the circle was for channelling communication between the living and the dead in the belief that the dead could somehow promote fertility. Its ethereal nature contributes to the otherworldly aura of the site.

The name Pha Taem (‘Cliff Painting’) refers to Thailand’s largest gallery of pre-historic rock paintings. Running 180 metres across the cliff face are more than 300 drawings of objects related to hunting and fishing. Estimated to be between 2,000 and 3,000 years old and arrayed in four groups, they depict elephants, tortoises, dogs, fish, fishermen, fish traps, cows, rice fields (a screen-like grid) and snakes. There are also hand prints. Several big fish, larger in proportion to the other paintings (one specimen is 1.4 metres long), resemble the giant catfish, (plaa beuk), the world’s largest fish at about 600 kilogrammes, and a species unique to the nearby Mekong River. Wavy lines may signify clouds, water, rain, or supernatural forces related to water similar to the legendary Naga — the Serpent King, a potent water symbol for peoples of the Mekong basin.

The paintings have been rendered in hematite, a natural pigment composed of soil, fat and tree gum that is found in many I-san burial sites.

A wealth of meanings have been ascribed to the paintings. Some archaeologists have postulated that they were totemic images associated with animistic rites. It is also thought that the ancients may have gathered here for fertility rituals. The most credible interpretation is that the drawings simply represent daily life. Aside from the wavy lines, these are depictions of real objects — not of items transmuted into mystical symbols but a record of farming and cultivation.

To whom the message was directed is another matter. Nearly 50 metres off the valley floor, they would have been clearly visible from the Mekong and Laos on the opposite bank. Perhaps, they were a statement of ownership and civic pride — a proclamation that “this village created this.”

The hand prints form another mystery. They may appear as part of a rite of passage since some hands obviously belong to children. The colour was applied by blowing the pigment from the mouth or through a bamboo pipe, spraying it over a real hand to create a negative image.

SAO CHALIANG

Situated three kilometres from Pha Taem is another intriguing formation: a series of stone “mushrooms” comprising columns and caps. The columns date from 180 million years ago while the umbrella-like capstones comprise a harder sandstone of the later Cretaceous period, 150 million years ago, a phenomenon common in the mountains of the Northeast. The local Suai people called these mushroom-like columns sa-liang, meaning "stone pillar," a word which later Thais transformed to Sao Chaliang.

	Amidst this arid landscape are several oases in the form of waterfalls and wildflowers. Nam Tok Saeng Chan (Moonlight Falls), 41 kilometres from Pha Taem is also called “Nam Tok Ruu” (Hole Falls), for the two-metre wide crescent hole through which the water drops eight metres into a pool below before flowing on to the Mekong. The water hitting against the tunnel resembles the moonlight against the earth’s surface, thereby inspiring its official name. Nearby Soi Sawan Sawan Waterfall originates from two streams which fall separately, creating the strands of a necklace that eventually merge.
	Atop the falls is Lan Hin Thung Dawk Mai, a series of six fields of beautiful wildflowers which bloom from late October to late February. Their colours range from silver through pink and include the Dusita, a purple insect-eating blossom.

Some of the most intriguing of I-san’s geological oddities are encountered on a boat cruise up the Mekong River from Haat Salueng Ban Song Khon in Khemarat, 80 kilometres north of Khong Chiam. After examining the riverside village and its beach, one moves upriver.

Akin to Pha Taem, but far more elaborate and evocative, is Phu Pha Toeb National Park near Mukdahan. Its mushroom rocks are 20 million years older than those at Pha Taem but the variety of its other formations is astounding. The dozens of oddly-shaped rocks have been given names—Turtle, Cow, Dragon—but one’s imagination runs rampant in deciding what they most resemble.

Most of the formations are sandstone with streaks of manganese. The majority are within a few metres of the park office. For the hardy traveller, the rewards for a long walk lie at the end of a long, smooth sandstone mantle 200 metres thick and large enough to land a small airplane.

At the summit are splendid views of the surrounding countryside. The flat rocks leading to a formation resembling a camel are raised lines like blood veins.

One emerges from a survey of these sites with the feeling of having touched something primordial. It is a feeling of having been present at the birth of the planet, prior to the emergence of humans, and it leaves one feeling remarkably tranquil despite the violent natural forces that shaped this alien landscape.

Contact information:
Tourism Authority of Thailand — Ubon Ratchathani Office
Tel: +66 (0) 4524 3770
Fax: +66 (0) 4524 3771
E-mail: tatubon@tat.or.th