Thailand has more than a hundred national parks and two of them turn up on almost every itinerary that leaves the beaches. Erawan is a waterfall west of Bangkok that climbs through forest in seven tiers of turquoise pools you can swim in. Khao Sok is a swathe of very old rainforest in the south, wrapped around a lake with limestone towers rising vertically out of it, where you sleep on a raft. They are completely different days and both are among the best things in the country away from the coast.
Erawan
What it is. A waterfall in a national park west of Bangkok, near the town on the river with the wartime bridge, climbing through forest in seven distinct tiers.
The pools at several levels are clear, turquoise, and swimmable, which is what turns a waterfall walk into an afternoon.
The fish in the pools nibble at feet, which is startling once and funny afterwards.
The climb is easy at the bottom and progressively rougher, with scrambling near the top. Ninety minutes up at a steady pace.
The crowd thins with height. The first two tiers are busy and the upper ones are frequently near empty, which is the whole trick to the place.
Take proper shoes, because wet rock and flip-flops account for most of the injuries here.
Khao Sok
What it is. An area of rainforest considerably older than the Amazon, in the southern peninsula, surrounding an artificial lake created by a dam.
The lake is the reason to come: limestone karst towers rising sheer out of green water, reached by longtail boat.
Raft houses float on the lake, simple structures where you sleep, swim off the deck, and go out at dawn.
The forest has genuine wildlife, including gibbons you will hear more often than see, hornbills and macaques.
Two nights is the shape that works: one at the entrance area, one on the lake, or two on the lake.
It is basic on the water. Limited power, cold showers, no air conditioning, and that is part of it.
Getting to each
Erawan is reached from the river town a few hours west of Bangkok, either as a very long day trip from the capital or, far better, as part of an overnight stay there. Our guide to Kanchanaburi covers the town, the bridge and the history that sits alongside the park.
Khao Sok sits between Surat Thani on the Gulf side and the Andaman coast, which makes it a natural stop when crossing the peninsula between the two coasts rather than a detour.
Both are served by organised trips, and Khao Sok in particular is easier arranged than assembled.
Practical notes
Park entry fees for foreign visitors apply at both and are payable in cash at the gate.
Upper tiers at Erawan close earlier than the park itself, so a late arrival means a shorter climb.
Plastic bottles are restricted or deposited at some park entrances, part of a genuine effort to keep them out of the water.
Leeches are a fact of a wet-season forest walk in the south, unpleasant and harmless.
Mosquito repellent matters at Khao Sok, particularly at dawn and dusk on the lake.
Do not feed the monkeys, which is how they learn to take bags.
Where these fit
Both work best as a break from beaches and cities rather than as day trips squeezed into them.
Khao Sok pairs naturally with a quiet Andaman island afterwards, and our guide to Koh Lanta covers the calmest of them, which is a good landing after two nights in the forest.
And for choosing when to come at all, since the rain determines both the waterfalls and which coast you should be on, our guide to the best time to visit Thailand covers the seasonal picture.
The short version
Climb past the busy lower tiers at Erawan to the quiet upper ones, swim in the pools, and wear shoes with grip rather than flip-flops. Ask about current water levels first, because a waterfall at the end of a dry spell is not the one in the photographs. At Khao Sok, sleep on the lake in a raft house rather than only visiting the park entrance, book it well ahead because capacity is small, and go out by boat at dawn when the mist is on the water. Both deserve a night rather than a rushed day.
