Khao Yai Thieng

History & Significance

Khao Yai Thieng is located in Khlong Phai Sub-district, Si Khiu District, Nakhon Ratchasima Province. The mountain borders several protected forest areas, including Khao Tian, Khao Khuan Lan, Pak Chong, and Mu Si forests. Historically, villagers began settling and farming corn here around 1974. In 1981, the Royal Forest Department allocated land plots to locals. Due to the rocky terrain being unsuitable for agriculture, some portions were later sold to outsiders for vacation homes. Today, the area is highly significant as a clean energy hub, featuring the upper reservoir of the Lam Takhong Cholabhathanana Power Plant, a pumped-storage hydropower facility managed by the Electricity Generating Authority of Thailand (EGAT).

Local lore tells the legend of Yai Thieng (Grandmother Thieng) and Pu Sing Dam (Grandfather Sing Dam), the very first settlers who cleared the forest to live here decades ago. After Yai Thieng passed away on the adjacent Khao Krajom mountain, a village headman in 1991 dreamed of an old woman asking him to exhume her bones. The villagers found the remains exactly as described, performed merit-making ceremonies, and established the Yai Thieng and Pu Sing Dam Shrine at the village entrance.

Highlights & What to See

• Giant Wind Turbines: The defining landmark of Khao Yai Thieng is the array of 12 massive wind turbines spinning gracefully against the sky, generating clean wind energy.
• Upper Reservoir: A scenic asphalt loop surrounds the mountaintop reservoir. It is a highly popular spot for renting bicycles or golf carts to enjoy the cool breeze, morning mist, and spectacular evening sunsets.
• Pha Yai Thieng Viewpoint: Situated 650 meters above sea level, this wide stone cliff offers breathtaking, unobstructed views of the Lam Takhong Reservoir and the surrounding wind turbines.

Visitor Information

Khao Yai Thieng is open daily from 06:00 AM to 06:00 PM. Admission to the site is free, though there are small rental fees for bicycles and golf carts if you wish to ride around the reservoir. On-site facilities include parking spaces and public restrooms. Visitors are advised to bring a light jacket, as the weather can get quite chilly, especially during the morning and winter months.

How to Get There

Khao Yai Thieng is located in Khlong Phai, Si Khiu District, Nakhon Ratchasima Province, overlooking the Lam Takhong Reservoir. It is easily accessible by car from Bangkok or Nakhon Ratchasima city via Mittraphap Road (Highway 2). Look for the access road leading up the mountain near the Lam Takhong area.