Jellyfish Lake, Togean Islands: How to Visit Mariona Lake

The Togean Islands have one of the world's very few swimmable stingless jellyfish lakes — usually called Mariona Lake (Danau Mariona), on a small island near Katupat in the central archipelago. You visit by boat trip from your resort (most central and eastern resorts run them), slip in with mask and snorkel, and float among soft golden jellyfish that have lost their sting through generations of isolation. It is routinely the non-diver highlight of a Togean trip — though numbers in the lake fluctuate, so read the honest caveat below.

Status as of June 2026: operator reports from 2024 describe a sharp jellyfish population decline; recovery unconfirmed — ask your resort for this month's reality before planning a day around the lake.

Last verified: June 2026.

What it is, and why the jellyfish don't sting

Mariona is a marine lake — a sea-water lagoon enclosed by limestone and jungle, connected to the ocean only through fissures in the rock. Cut off from predators, its jellyfish population evolved with no need for potent defenses: their sting is so reduced that humans cannot feel it. The same phenomenon made Palau's Jellyfish Lake famous; the Togeans' version has a fraction of the visitors.

On a good day the experience is surreal — warm, greenish, glass-calm water with pulsing jellyfish from the surface down as far as you can see. Density varies with season, weather and where in the lake the swarm is sitting; some days you swim through clouds of them, other days you go looking. One honest caveat: dive-operator reports from 2024 described a sharp drop in the lake's jellyfish numbers, so ask your resort what the lake has been doing recently before building a day around it. Naming note: you will also hear "Togean jellyfish lake" and see other lakes mentioned online — Mariona near Katupat is the one the resorts run trips to.

How to visit

There is no road, ticket office or jetty queue — this is the Togeans. You go by chartered boat trip:

• From Katupat-area resorts (Fadhila, Bolilanga, Uma) the lake is close — a short boat hop plus a brief walk over the limestone to the water.
• From Malenge resorts (Sandy Bay, Bahia Tomini, The Cliff, Lestari and others) it is a standard half-day or full-day trip, usually combined with snorkel stops.
• From Kadidiri it is a longer full-day outing — combine it with Katupat village or reef stops to make the fuel worthwhile.

Cost is per boat, shared among passengers — figure roughly Rp 100,000-300,000 per person depending on group size and distance (resorts quote per-boat prices; European-run places sometimes quote ~€15 pp). Park/village fees, where charged, are small and handled by your boat crew.

Bring mask, snorkel, and water shoes for the walk in. Go in the morning if you can — calmer light, fewer other boats (not that there are ever many).

The rules: swim like a guest

The jellyfish are defenseless and the lake is a closed ecosystem. The rules are simple and matter:

• No fins. A fin kick shreds jellyfish. Every reputable resort enforces this; swim gently instead — the lake is calm and you do not need them.
• Don't touch, don't lift them out of the water. Handling damages their delicate tissue.
• Skip the sunscreen (or use only reef-safe, well rubbed-in, applied long before). Chemical slicks accumulate fast in an enclosed lake. A rash vest is the better answer.
• No jumping or diving in from the rocks — ease in at the entry point.
• Drone and camera people: by all means, but the rule of thumb is the jellyfish set the pace, not the shot list.

What to combine it with

Trips almost always bundle the lake with nearby stops, and the classics are good ones:

• Karina Beach — a much-loved white-sand swimming beach in the central archipelago; the standard pairing on Katupat-area trips.
• Reef snorkel stops on the way out or back — your boat crew will know the day's calm side.
• Pulau Papan stilt village and its boardwalk, if you are coming from the Malenge side.
• Some Bomba- and Kadidiri-based itineraries roll the lake into a full central-islands day with Wakai or Katupat village.

If you are choosing where to stay partly for the lake, base yourself in the Katupat-Malenge belt — see our where to stay guide.

FAQ

Where is the jellyfish lake in the Togean Islands?

On a small island near Katupat village in the central archipelago — usually called Mariona Lake (Danau Mariona). Resorts across the central and eastern Togeans run boat trips there.

Do the jellyfish really not sting?

Their sting is so weakened by generations of isolation that people cannot feel it. Swimming among them is harmless to you — the protection rules exist to keep you harmless to them.

How much does a jellyfish lake trip cost?

Boats are chartered per trip and shared: expect roughly Rp 100,000-300,000 per person depending on group size and starting point (about €15 per person is a common quote from the closer resorts).

Can you scuba dive in the jellyfish lake?

No — it is a snorkeling site, shallow and enclosed, and tanks/fins would damage the jellyfish. Mask and gentle swimming only.

Is it always full of jellyfish?

No — numbers fluctuate with season and conditions, the swarm moves around the lake, and dive-operator reports from 2024 described a sharp population decline, so manage expectations. Many visitors still report magical days; some find the lake quiet. Morning trips in calm weather give the best odds — ask your resort what the lake has been doing lately.

Is the Togean jellyfish lake still worth visiting in 2026?

Yes — as part of a boat day with snorkel stops, not as the sole reason for the trip. Operator reports from 2024 described a sharp drop in jellyfish numbers and recovery is unconfirmed as of June 2026, so density on the day can range from clouds of jellyfish to a quiet lake. Ask your resort what the lake has been doing this month, and pair it with Karina Beach or reef stops so the day stands on its own either way.