The Blue Cave: the Swim, the Boats and the 2026 Rules

The single most important fact on.

The single most important fact on this page: as of the 2026 season change, announced as starting 21 May, boats are no longer allowed inside the Blue Cave. Before that, skippers nosed their bows straight into the glow. Now they moor at the mouth and you swim in when the skipper judges the swell safe.

This matters more than any price difference between tours, because it changes what the trip depends on. A calm morning means an easy float through the entrance. A choppy one means the skipper may shorten the swim or, on the worst days, move the stop.

No source publishes a wave-height cutoff or a formal rulebook, so the skipper's word is the rule. That is also why you should treat any photo of a boat inside the cave as an archive shot, not a promise. Operators have adjusted their listings to say boats no longer enter, and our own checks of the three tours on this page confirm that language.

If the swim-in sounds like too much, be honest with yourself before booking: the value of the trip is the water. A useful backup on a rough day is one of the rainy day ideas in Kotor or the walls climb in our fortress guide.

Our Lady of the Rocks

The first stop is usually Gospa od Škrpjela, an artificial island of just 0.38 hectares that generations of seamen built by scuttling old ships loaded with stone and by laying a rock on the spot after every successful voyage. The legend says fishermen found an icon of Madonna and Child on the rock there, and every 22 July at sunset the fašinada procession still rows out to throw stones and widen the island. Inside, Tripo Kokolja of Perast painted 68 baroque works for the church, and the votive embroidered hanging by Jacinta Kunić-Mijović took 25 years of embroidery, worked in gold, silver and her own hair.

On the tour stop you get about 20 minutes, which is enough for the church and a lap of the quay. Two practical lines matter: island admission has been €5 per guest in cash since April 1, 2026, paid on the island, and there is a dress code, so island entry in swimwear is not allowed. Our full Our Lady of the Rocks guide and the Perast page cover the rest.

The Submarine Tunnel at Rosa

Next the boat slides into a tunnel cut for the Yugoslav navy, a relic of the Cold War when submarines hid inside the bay's cliffs. The visit lasts about 10 minutes. It is a strange, echoing interlude between the church and the open water, and it photographs well when the skipper kills the engine.

There is nothing to buy and nothing to climb, just rock, water and a story. It is one of the reasons the speedboat circuit earns its price over a plain bay cruise: no land route reaches it.

Mamula Fortress

The circuit then passes Mamula, the fortress island at the bay's mouth. The Austro-Hungarians built the fort, and the Italians used it as a Second World War prison, a history that gives the pretty outline a darker weight. The boat does not land.

You get the view from the water, which is honestly the best angle, with the walls rising straight from the sea. Beyond Mamula the bay opens to the Adriatic, and the cave waits on the Herceg Novi side of the entrance.

The Blue Cave Itself

The payoff is a cave with no gate and no fee, reached only by water. You will get around half an hour of swim time here on the standard circuit. Boats hold at the mouth, you slip in over the sill, and the light through the entrance does the rest.

Bring the things no tour provides: a towel, a dry layer for the ride back and a strap for your glasses. Skipper calls the swell, so treat the 30 minutes as a minimum promise rather than a guarantee. Nobody publishes the exact depth at the entrance, so if you are a weak swimmer, tell the crew before you leave the dock.

The cave's blue comes from sunlight.

The cave's blue comes from sunlight entering through the mouth and the water, so midday and early afternoon give the strongest colour. That is also when the tour fleet is thickest, because most circuits run a morning and a midday rotation. The honest trade is this: go early for calmer water and emptier caves, or go midday for the deepest blue.

Sources do not publish an official best hour, so this is scheduling logic, not a rule. Season matters more than hour. The bay's summer highs average 29.6 C in July and 29.7 C in August, with the driest months at 62 mm of rain in July and 84 mm in August, which is when the swell and cancellation risk are lowest.

Spring and autumn work too, but the sea cools and the weather turns faster. Winter trips are not what the operators advertise and the swim becomes the question mark. For month-by-month planning, see our Kotor weather page and the best time to visit Kotor breakdown.

If your dates sit near a cruise day, remember that around 523 cruise calls are scheduled for Kotor in 2026 and the waterfront gets busier around them, which you can track on our cruise port page.

The ride from Kotor to the.

The ride from Kotor to the cave area takes about 20 to 25 minutes each way, mostly at speed in open water once you clear the Verige Strait, which is only 340 m wide at its narrowest. Speedboats bounce. Both major speedboat operators state plainly who should not book: the three-hour tour is not suitable for pregnant women, people with back problems, wheelchair users, people over 260 lb (118 kg) or anyone prone to seasickness, and the four-hour tour excludes babies under one, wheelchair users, people with mobility impairments, pregnant women and people with back problems.

No toilet sits on board either boat, so the crew will tell you to go before departure. The kayak trip has its own filter: it requires basic swimming fitness and is not a beginner sit-down excursion. Take motion sickness tablets before you board, not on the water.

If the open-sea leg worries you, the full-day covered bay cruise is the gentlest hull, though its Blue Cave leg is itself subject to weather. Our Kotor with kids page has more on what younger swimmers can handle, and Kotor safety covers the general picture.