Khun Si Waterfall, Koh Samui: The Local's Guide

Khun Si Waterfall is the one nobody plans a day around, which is exactly why we like it. Our own waterfalls guide already named it the small one nobody drives to, tucked in the hills behind Maenam and Bophut. Here's the part that guide didn't have room for: the viewpoint mix-up, the walk, and what's actually waiting at the top.

The viewpoint and the waterfall are not the same stop

Search for Khun Si and you'll get two results tangled together: Khun Si Viewpoint, a lookout over the hills, and Khun Si Waterfall, which shares the name and the neighbourhood but not the parking spot. You drive to the viewpoint first. The waterfall is a separate walk from there, down through the trees, marked by nothing grander than a plain wooden sign. If you turn up expecting the fall to be right where you parked for the view, you'll spend ten minutes convinced you got the wrong hill.

Finding it

Khun Si sits in the hills straddling Maenam and Bophut, up through durian plantations, which is the detail that tells you you're in the right place before the sign does. Put "Khun Si Viewpoint" into Google Maps rather than the waterfall itself. From the viewpoint, the path down is short but properly a path, not a boardwalk, so trainers over sandals here.

None of the write-ups mention a cafe or an operator at the bottom, the kind Tan Rua has built up the road. Just the path, the plantation, and the sign.

The walk and what's at the top

It's half a kilometre out and back with about 38 metres of climb, so half an hour to an hour if you stop for a swim. Short on paper, steep in practice: terraced rock, packed earth, and a real climb for such a small distance. TripAdvisor's advice is the honest kind: go early, wear closed shoes, and expect it slippery in places. Get there before the day trippers find the viewpoint car park and you'll likely have the trail to yourself the whole way down.

The reward is terraced rock and a pool at the top, not one dramatic drop. It's a smaller, quieter cousin of Hin Lad, not a rival to it. Kohplanner claims there's a small cave tucked behind the falls if you go looking. We haven't found it. In our defence, we've only looked once, in flip-flops we should not have worn on a slippery rock trail.

Can you swim there?

Yes, in the pool at the top, and it's a genuine swim rather than a photo-and-leave. Go in the dry season, December through March, for the safest footing on the way down and the clearest water once you arrive. Heavy rain earlier in the wet season fills the pool faster but makes the rock underfoot a different kind of dangerous, so if it's been pouring for days, this isn't the walk to test your balance on.

Is Khun Si Waterfall worth it?

If you want to feel like you found something, yes. This isn't a stop with a zipline and a treehouse cafe bolted onto it like Tan Rua; it's a quiet hill path, a plantation, and a pool you'll likely have to yourself. If you want the biggest, most reliable waterfall day on the island, that's still Na Muang, not this one. Khun Si is the stop for people who've already done the famous ones and want the version without the tour buses.

Come back down the hill afterwards and rinse the durian-plantation dust off in a pool that doesn't depend on the season, over at Chaweng Noi.

Quick answers

Is Khun Si Waterfall worth visiting?

Yes, if you want a quiet short hike without the crowds or the tour infrastructure other Samui waterfalls have. It's not the tallest or most dramatic fall on the island, just the emptiest.

How do I get to Khun Si Waterfall?

Drive to Khun Si Viewpoint, in the hills between Maenam and Bophut, then take the short marked path down through the durian plantation to the falls. The waterfall and the viewpoint are two separate stops, not one.

How long is the walk to Khun Si Waterfall?

About half a kilometre out and back, 30 to 60 minutes with a swim, on a steep path with a real climb packed into a short distance.

Can you swim at Khun Si Waterfall?

Yes, in the rock pool at the top. Go in the dry season (December to March) for safer footing and clearer water.

What is the most famous waterfall in Koh Samui?

Na Muang, and our waterfalls guide covers why it's the one every tour books first.