Thailand's National Parks

Thailand's national park system is one of Southeast Asia's most extensive, protecting landscapes ranging from limestone mountains and monsoon forests to coral reefs and mangrove swamps. With 154 national parks (130 terrestrial, 24 marine) and 58 wildlife sanctuaries covering approximately 18% of the country's land area, Thailand has invested heavily in conserving its natural heritage — even as development pressures continue to grow.

History

Thailand's first national park — Khao Yai — was established in 1962, inspired by the American national park model. Growth was slow at first but accelerated dramatically from the 1980s onwards, driven by environmental awareness and the devastating deforestation of the 1970s–80s which reduced forest cover from roughly 54% to under 30%.

The 1989 logging ban was a watershed moment. By banning all commercial logging in natural forests, Thailand signalled that conservation would take priority over extraction. Since then, forest cover has stabilised at approximately 31–33% and is slowly increasing through reforestation programs.

UNESCO World Heritage Sites

Thailand has five natural UNESCO World Heritage Sites:

Thungyai-Huai Kha Khaeng Wildlife Sanctuaries (1991) — The crown jewel. 6,222 km² of pristine tropical forest in the Western Forest Complex. One of mainland Southeast Asia's last great wildernesses. Not open to general tourism — access is strictly controlled. Contains tigers, elephants, gaur, bears, and hundreds of bird species.

Dong Phayayen-Khao Yai Forest Complex (2005) — Five protected areas spanning 6,155 km² across the mountains northeast of Bangkok. Includes Khao Yai National Park (the most visited park in Thailand). Important tiger and elephant corridors.

Kaeng Krachan Forest Complex (2021) — Thailand's newest World Heritage Site. Three protected areas covering 4,089 km² along the Myanmar border, including Kaeng Krachan National Park (Thailand's largest by area). Exceptional birding — over 400 species recorded.

Top Terrestrial Parks

Khao Yai National Park

Location: Nakhon Ratchasima/Saraburi/Nakhon Nayok (3 hours northeast of Bangkok)
Size: 2,168 km²
Highlights: Wild elephants, gibbons, hornbills, Haew Narok and Haew Suwat waterfalls (the latter featured in The Beach), night safari drives, ancient tropical forest.
Best time: November–February (cool season). Rainy season can make roads impassable.
Accessibility: Excellent. Paved roads, visitor centres, accommodation, guided walks.

Khao Sok National Park

Location: Surat Thani (inland from the Andaman coast)
Size: 739 km²
Highlights: One of the world's oldest tropical rainforests. Cheow Lan Lake — a stunning man-made lake surrounded by limestone karst towers, with floating raft-houses for overnight stays. Gibbons, hornbills, langurs, elephants (rarely seen). Limestone caves. Rafflesia (the world's largest flower, blooming January–March).
Best time: December–April (dry season)
Accessibility: Good. Tour operators in Surat Thani and Khao Lak offer packages.

Doi Inthanon National Park

Location: Chiang Mai (90 minutes southwest of the city)
Size: 482 km²
Highlights: Thailand's highest peak (2,565m). Two royal stupas at the summit. Cloud forest and sphagnum bog at altitude — a habitat unique in Thailand. Exceptional birding (380+ species). Wachirathan and Mae Ya waterfalls. Hmong and Karen hill tribe communities.
Best time: November–February. Season matters: the summit can be cold (0–5°C in December–January).
Accessibility: Excellent. Paved road to the summit. Easy day trip from Chiang Mai.

Erawan National Park

Location: Kanchanaburi (western Thailand)
Size: 550 km²
Highlights: The spectacular Erawan Falls — seven tiers of cascading waterfalls through tropical forest, with emerald-green pools for swimming at each level. Named for the three-headed Hindu elephant god (the seventh tier supposedly resembles Erawan). Wild elephants in the broader park.
Best time: November–May (falls are best during late rainy season/early cool season when water flow is strongest but trails are dry).

Kaeng Krachan National Park

Location: Phetchaburi (southwest of Bangkok, bordering Myanmar)
Size: 2,914 km² (Thailand's largest national park)
Highlights: Exceptional birdwatching — 400+ species including broadbills, pittas, and hornbills. Wild elephants. "Sea of mist" viewpoints in cool season. Pala-U waterfall. Remote wilderness feel.
Best time: November–March.

Khao Sam Roi Yot National Park

Location: Prachuap Khiri Khan (south of Hua Hin)
Size: 98 km²
Highlights: "Mountain of 300 Peaks" — dramatic limestone pinnacles rising from coastal marshes. Phraya Nakhon Cave — the park's star attraction, a collapsed cave with a royal pavilion bathed in sunlight streaming through holes in the ceiling. One of Thailand's most photographed natural sites.

Top Marine Parks

Mu Ko Similan National Park

Location: 80km offshore from Phang Nga, Andaman Sea
Size: 140 km² (9 islands)
Open: Mid-October to mid-May only
Highlights: World-class diving and snorkelling. Granite boulders, swim-throughs, walls. Whale sharks, manta rays, leopard sharks. Spectacular topside scenery (Sail Rock viewpoint).

Mu Ko Surin National Park

Location: 60km offshore from Phang Nga, near Myanmar border
Open: Mid-October to mid-May only
Highlights: Exceptional shallow-water snorkelling over pristine hard coral reef flats. Moken sea gypsy village. Remote, less visited than the Similans.

Ang Thong Marine National Park

Location: 42 islands in the Gulf of Thailand, west of Ko Samui
Highlights: Dramatic limestone islands rising from blue water. Emerald Lake (Thale Nai) — a saltwater lagoon inside a collapsed cave. Kayaking, snorkelling, viewpoint hikes.

Tarutao Marine National Park

Location: Satun, far southern Andaman Sea
Size: 1,490 km² (51 islands)
Highlights: Wild, undeveloped islands including Ko Tarutao (former political prison) and Ko Adang. Excellent wildlife (monitor lizards, langurs, hornbills). Empty beaches. Minimal tourist infrastructure.

Practical Information

Entry fees: 200–400 THB for foreign adults (200 THB children). Thai nationals pay 20–40 THB. Annual passes available.
Accommodation: Most parks offer bungalows, dormitories, and camping. Book via the DNP (Department of National Parks) website — popular parks (Khao Yai, Erawan) book out on weekends.
Rules: No feeding wildlife, no littering, no single-use plastics (banned since 2018), no drones without permission, no off-trail hiking. Fines are enforced.
Guides: Required in some parks and on specific trails. Available at visitor centres.