Ton Sak Yai (Giant Teak Tree) Forest Park

Ton Sak Yai is a single, extraordinary teak tree in the Nam Pat district of Uttaradit — reputedly the largest in the world. It’s around 1,500 years old, with a trunk nearly 10 metres in circumference, and it gives its name to the national park around it (once known as Khlong Tron). Entry is free, and a wooden boardwalk loops the base so you can take it in from every angle.

The tree

This is the reason to make the trip: a teak of a scale that’s hard to picture until you’re beneath it. It stands about 37 metres tall today, though it was closer to 48.5 metres before a storm took its crown — and its girth of 9.87 metres would take several people linking hands to encircle. The boardwalk keeps visitors off the roots, so you circle the trunk on a raised loop through quiet forest rather than tramping the ground around it. It’s a short visit — a stop, not a hike — but a genuinely memorable one.

Insider Tip: Come in the morning for cooler air and softer light through the canopy, and combine it with the wider Ton Sak Yai National Park (waterfalls and forest trails) so the long drive out earns a full half-day.

Getting there

The tree is deep in Nam Pat district, roughly 90 km east of Uttaradit town — a 1.5 to 2 hour drive on winding roads. There’s no practical public transport, so you’ll want your own vehicle or a hired car. Entry to the forest park is free.

Watch out: It’s remote and off the usual tourist trail, so plan the drive and fuel accordingly, and bring insect repellent and water. Stay on the boardwalk — stepping off to get closer damages the roots the barrier is there to protect.

Ton Sak Yai Forest Park is at Nam Khrai, Nam Pat District, Uttaradit 53110. View on Google Maps.