Sok Ry squatted in the bushes and watched for more than an hour as rock climbers scaled the 28-meter-high, jagged rock face known as Phnom Oh Lok.
When someone asked him if he wanted to try, the 14-year-old thought for a few seconds and then, silent and expressionless, walked over and stepped into a climbing harness.
While the experienced climbers wore special shoes and chalked their hands for better grip, Ry didn't need any technical gear; he effortlessly climbed to the top barefoot and chalk-free.
Located on two big slabs of rock just off National Road 6, about 50 kms north of Phnom Penh, in Kampong Cham province, the climbs were "set" by Ryan Sinclair, an American in Cambodia doing research for his doctorate. An avid climber, he lugged his bag of climbing equipment along with him when he arrived in March 2004.
He noticed the promising-looking rocks, known locally as Phnom Oh Lok, or "No More Monks Mountain" in English, about three months ago and stopped to "scope them out."
Aside from soloing - for adventure junkies who climb without safety gear - there are two schools of rock climbing, Sinclair explains, each defined by a different use of safety gear. Sport climbing involves bolts being permanently drilled into the rock; traditional climbing involves fixing temporary safety anchors into the rock face and then removing them as climbers make their way up.
On his initial ascent, Sinclair drilled bolts into the rock face. The absence of natural cracks in the rock meant that bolts had to be permanently drilled in order to make climbing safe. He did another route a few weeks back, and now he and his friends have two sport climbs at Oh Lok.
On the second, more challenging route, Ry gives it everything. After winning a long battle with a difficult overhang section, the shy youngster finally cracks a smile. Once making it to easier holds, he puffs with pride and exertion.
He may be the first official Cambodian rock climber, but if he wants to continue, there are limitations to the growth of the sport that need to be overcome.
Lack of equipment, Sinclair says, poses the greatest challenge, and danger, to rock climbing in Cambodia.
The climbing bolts in Phnom Oh Lok, for example, were manufactured and tested under strict international standards and can hold a maximum of 3,600 kilograms.
He says the bolts probably could be replicated here, but the steel quality may not be as high and there is no mechanism for safety testing.
So for now Sinclair must rely on friends travelling from abroad to bring new bolts and safety equipment.
Speaking about the sport's future in Cambodia, Sinclair says at least 10 more climbs could be set on Phnom Oh Lok, but the real rock climbing potential Ohaits in Kampot province.
The limestone karsts in Kampong Trach district are similar to those found in southern Thailand, which has long been a rock-climbing mecca and drOhs thousands of climbers each year.
Sinclair has already made plans to climb at Kampong Trach with some friends. He has surveyed the formations, taken photos and has several possible climbs in mind. He's just waiting for someone to arrive with a wish list of new safety gear.