Blue Pool (Sa Nam Phut): Krabi's Serene Forest Pool Worth the Walk

What Is the Blue Pool?

Blue Pool, known in Thai as Sa Nam Phut, is a small natural pool within the forested interior of Khlong Thom District. Unlike the Emerald Pool a short walk away, which draws consistent crowds of swimmers, Blue Pool sits at the end of a forest trail and imposes a strict no-swimming rule. That constraint shapes the entire experience: visitors arrive, go quiet, and look.

The water's color is the obvious draw. The pool holds a deep, almost electric blue-green tone caused by minerals dissolved in the warm spring water interacting with light filtering through the forest canopy. The color shifts noticeably depending on the time of day and the angle of the sun, which is one reason photographers who arrive mid-morning often get a different result than those who reach it closer to midday. The surrounding trees lean in close, and the stillness of the water gives the pool an almost reflective quality that photographs well but feels genuinely unusual in person.

When and How to Get There

Blue Pool is only open to visitors during the dry season, generally November through April. Outside those months, the surrounding forest path and the pool area are closed. A secondary source reports daily visiting hours of approximately 10:00 to 15:30 during the open season, though this has not been independently confirmed and may vary. Arrive well before midday to account for the walk and to leave time at the pool itself.

Khlong Thom District sits roughly 45 kilometers southeast of Krabi Town along Highway 4, in the same direction as Koh Lanta. There is no direct public bus service to the Emerald Pool or Blue Pool trailhead. Most travelers arrive by rented car or motorbike, or by booking a half-day tour out of Krabi Town or Ao Nang. Songthaews (shared pickup trucks) from Krabi Town can take you as far as Khlong Thom town, from where you would need onward transport. A private taxi or Grab from Krabi Town is a cleaner option if you are not on a tour.

The Walk In: Forest Path and First Impressions

Blue Pool is reached on foot from the Emerald Pool area via a forest trail. The path runs through lowland rainforest, and depending on conditions underfoot, it can be muddy or uneven in places. Wear closed shoes or sturdy sandals with grip — flip-flops make this walk awkward and occasionally slippery. The path is not long, but it is not paved, and the forest vegetation closes in on both sides, which lends the walk a sense of genuine transition between the main visitor area and something more remote.

The sounds on the trail are worth paying attention to. Birds call from the canopy, insects are audible throughout, and the ambient noise of the main Emerald Pool area fades quickly once you are on the path. By the time the Blue Pool comes into view, the contrast with the busier site behind you is noticeable. The pool itself sits in a small clearing where the light changes and the air feels slightly warmer from the geothermal activity below.

The path is not formally signposted at every junction, so follow other visitors or ask staff at the Emerald Pool entry point for directions before you set off. Accessibility information is limited — the available sources do not confirm wheelchair access or facilities for visitors with mobility constraints along the forest trail.

At the Pool: What You Actually See

The pool is smaller than most first-time visitors expect. That is not a criticism — the scale is part of what makes it feel intimate rather than spectacular in the grand-landscape sense. The color ranges from a pale aquamarine near the shallows to a deeper blue-green at the center, with slight variations visible across the surface as the sun moves.

The pool sits within the same broader ecosystem as the Emerald Pool and the Khlong Thom Hot Springs, all of which are part of the protected forest and wetland zone in Khlong Thom. The mineral-rich water that gives these pools their remarkable colors emerges from underground sources heated by geothermal activity. At Blue Pool specifically, swimming is prohibited to protect the area.

Mornings produce the clearest light for photography. By midday, direct sunlight filters more intensely through gaps in the canopy, creating bright patches on the water surface that can wash out the blue-green tone in photographs. If you arrive between 10:00 and 11:30, you often catch a balance of soft light and reflective stillness. Later in the afternoon, the forest shade deepens and the pool takes on a darker, more mysterious tone — less photogenic for color, but atmospheric in a different way.

Combining Blue Pool with the Emerald Pool

Most visitors to Blue Pool also visit the Emerald Pool on the same trip, and the combination is logical. The Emerald Pool is larger, allows swimming in designated areas, and tends to draw more people. Blue Pool functions as a quieter coda to that experience. The admission arrangement for the area should be confirmed on arrival. The Khlong Thom Hot Springs are also nearby and can be incorporated into the same half-day if your transport allows the flexibility.

If you are planning this as part of a longer day out from the coast, the area sits conveniently along the route described in guides to day trips from Krabi. Travelers staying in Ao Nang or Krabi Town typically arrange transport through their accommodation or a local tour operator.

Who Should Reconsider This Visit

Blue Pool is genuinely worth the walk for visitors who value quiet natural environments and do not need an activity-based payoff at the end. But it is not for everyone. Travelers who came specifically to swim will find the no-swimming rule frustrating, and the pool is small enough that if your expectations are built around a dramatic landscape, the reality may feel modest. Those with limited mobility should check accessibility conditions before committing to the forest trail.

The seasonal restriction also matters. If you are visiting Krabi between May and October, Blue Pool is closed, and this trip is simply not possible. During the shoulder periods around the open season, confirm current access status locally before making the journey out to Khlong Thom. The drive is not long, but it is far enough that an unnecessary round trip is worth avoiding.

Practical Notes

• Open season: November to April. Daily hours approximately 10:00–15:30 (unconfirmed — verify locally).
• Reported admission: ฿400 for foreign adults, ฿200 for foreign children, as part of the Emerald Pool area ticket. Confirm on arrival.
• No swimming permitted at Blue Pool under any circumstances.
• Wear closed shoes or grip sandals — the forest trail can be muddy.
• Bring water, sunscreen, and insect repellent. There are no facilities at Blue Pool itself.
• Photography is the primary activity. A standard smartphone camera works well in the right morning light.
• Do not apply sunscreen or insect repellent near the pool water Avoid applying sunscreen or insect repellent near the pool water.