Koh Rong to Pleiku: Coastal Jungles to Highland Mists

Koh Rong, a tropical island in the Gulf of Thailand, and Pleiku, a highland city in central Vietnam, are separated by about 700 kilometers of road that weave through tropical forests, rubber plantations, and mountain passes. The journey begins on the island’s sandy tracks (the island’s main road remains unpaved), so factor in time to reach the ferry pier at Koh Touch on the island's west coast. From there, it's a 45-minute ferry to Sihanoukville port, then an 8- to 10-hour drive eastward.

This route crosses two international borders at the Prek Chak–Xa Xia checkpoint, joining Cambodia’s National Road 4 and Vietnam’s National Highway QL14. Along the way, you transition from Cambodia’s flat Mekong floodplains to Vietnam’s Central Highlands, with an elevation gain of nearly 1,200 meters—noticeable in both temperature and vegetation.

Consider that while driving directly is possible, a popular alternative is to fly from Sihanoukville to Ho Chi Minh City and then connect to Pleiku, saving over 12 hours of driving. But if you crave overland adventure, read on.

Leaving Sihanoukville, you'll pass through the dense forests of the Cardamom Mountains, a region famous for its biodiversity. As you climb towards Pleiku, the landscape transforms into undulating hills of red basalt soil, where robusta coffee and pepper vines grow. The route passes within 100 km of the world heritage site of Preah Vihear Temple in Cambodia, but it's a detour northward; a closer UNESCO site is the My Son Sanctuary, located about 250 km south of Pleiku, not directly on the route—consider a side excursion if time allows. However, the highlight of the drive is the Central Highlands, known for their volcanic lakes and misty mornings.

The local commerce thrives on agriculture: you'll see roadside fruit stands selling dragon fruit, mangosteen, and durian in season. In Vietnam, coffee shops (cà phê) abound, serving robusta brewed with condensed milk. As you approach Pleiku, look for stalls selling “banh mi” and grilled rice paper, a regional snack. The highland specialty is “can” wine, a rice wine often consumed from a jar with bamboo straws, which makes a unique souvenir.

The route involves a mix of highways and secondary roads. From Sihanoukville, take National Road 4 north to Phnom Penh—this is a multilane highway in good condition. After Phnom Penh, head east on National Road 1 towards the Bavet border crossing. In Vietnam, continue on QL14 (also known as the Ho Chi Minh Highway) through Binh Phuoc and Dak Nong provinces, finally reaching Pleiku in Gia Lai province.

• Fuel stations are plentiful every 50-60 km in Cambodia and every 30-50 km in Vietnam, but in rural highland stretches, plan to fill up at larger towns like Phnom Penh or Buon Ma Thuot (which you'll bypass slightly) or Dak Lak.
• Border crossing hours are typically 7 AM to 8 PM (local time), and you'll need a valid passport, vehicle registration, and international driving permit. Vehicle insurance can be purchased at the border (about $30 for Vietnam).
• Tolls in Vietnam are minimal: expect about 120,000 VND ($5) for the entire stretch on QL14.
• Internet coverage is strong in Cambodian cities but can be sporadic in highland areas; get offline maps for navigation.

Both countries drive on the right, but road safety differs. Cambodian roads are more chaotic—watch for motos and overtaking trucks. In Vietnam, the QL14 is a two-lane road with occasional potholes, especially in mountain stretches; drive defensively. The maximum speed limit in Vietnam is 80 km/h, but in practice you'll average 50 km/h due to curves and traffic.

For families, the route is family-friendly with regular rest stops that have clean toilets and playgrounds, especially at Vietnam’s highway rest areas. In Cambodia, the highway between Phnom Penh and Bavet has many family-run eateries. Ensure kids are buckled up, and take breaks every two hours to stretch.

Pets are allowed but may require a health certificate and vaccination record when crossing borders. Most hotels in Pleiku and Sihanoukville are pet-friendly, but always confirm in advance. Carrying a pet carrier is advisable for rest stops.

For fatigue management, plan overnight stops at Phnom Penh and Buon Ma Thuot (the latter is a slight detour but offers a nice break). The total driving time, excluding stops, is about 14 hours, so spread over two days. The best stops Koh Rong to Pleiku include the riverside town of Kampong Cham, the coffee capital of Buon Ma Thuot, and the scenic Bo Ruong Waterfall near the border.

Before you set off, consult how to find the best stops and hidden gems between cities. If you're wondering is it worth driving Koh Rong to Pleiku, the answer lies in the immersive experience of the highlands, though it's a long haul. For a quicker connection, flying is option. But if you drive, take the time to discover things to do between Koh Rong and Pleiku, which include visiting indigenous villages and waterfalls.