Khao Ang Rue Nai Wildlife Sanctuary

Khao Ang Rue Nai Wildlife Sanctuary is one of eastern Thailand’s largest protected areas — about 643,750 rai (roughly 1,030 sq km), gazetted in 1977, spanning the border of five provinces: Chachoengsao, Sa Kaeo, Rayong, Chanthaburi, and Chonburi. The main visitor entrance and headquarters sit off Highway 3259 in Tha Takiap district, Chachoengsao, about two hours from Bangkok. Entry runs 200 THB for foreign adults (100 THB children) and 20 THB for Thai adults (10 THB children), daily 08:00-16:00.

This is a working sanctuary managed for the elephants, gaur, and hornbills that live in its interior, not a manicured park built around visitor traffic. Marked trails near the headquarters lead through forest and grassland, past a waterfall — often called Namtok Ang Rue Nai or Namtok Bo Thong — that runs year-round. Birdwatchers have a reasonable shot at hornbills and Siamese fireback pheasants; larger mammals like gaur, sambar deer, and elephants are present but genuinely wild, so sightings are a bonus rather than something to expect. June and July bring a butterfly season in the forest clearings, when large numbers gather in the damp ground near streams.

Insider Tip: Come for the trails and the waterfall rather than betting on big-mammal sightings — rangers here manage the sanctuary for conservation first, and facilities stay deliberately minimal to match.

Watch out: As a protected sanctuary rather than a municipal park, trail access can be restricted without much notice during active patrols or heavy rain. Call ahead if you’re travelling any distance, especially in the wet season.

Overnight stays are possible: a handful of houses sleep 4-6 people, and there’s a camping area where you bring your own tent. Both need to be booked ahead through the sanctuary office rather than arranged on arrival. Bring insect repellent, water, and sturdy shoes — there’s no shop at the trailhead.

The sanctuary’s Sa Kaeo side has its own trailhead at Namtok Khao Ta Krup, a five-tier waterfall that charges the same fee tiers. Closer to the Chachoengsao entrance, Krabok Khu Wildlife Breeding Centre runs a separate crocodile and reptile conservation programme. The Chachoengsao destination guide covers the wider province.