Zante Mare · Agios Sostis harbour, Laganas Bay
Zante Mare collects you from your hotel, takes you out of Agios Sostis on a semi-yacht speedboat and splits three hours between the turtle waters of Laganas Bay, the Keri sea caves and the beach on Marathonisi. Pick it for the balance: real swim time at two of the best spots on the south coast, with the transfer handled for you.

Zante Mare runs this trip from Agios Sostis, the small harbour at the western end of Laganas beach, next to Cameo Islet. A van picks you up, the transfer takes about 20 minutes, and you board a semi-yacht speedboat under the company's blue flags. The route covers the whole southern corner of the island: the turtle waters of the bay, the white cliffs and arches at Keri (the listing calls them the Kamares), a swim stop on Marathonisi and a photo stop at Cameo on the way back.
The turtles are the part to set your expectations on. Loggerheads feed and rest in Laganas Bay from spring to autumn, and the boat slows to look for them in Zone B of the National Marine Park, where the speed limit is 6 knots. Guests report seeing one or a few, often for a minute or two as a head comes up to breathe. One wrote that they "saw one turtle that breached the surface". The listing also mentions monk seals. Count that as a rare bonus, nothing more.
Two caveats. A speedboat bumps, and the listing rules it out for pregnant women, people with back problems and anyone prone to seasickness. And the captain can change the order of stops for wind or swell, which is common on the exposed Keri side. The 6 pm departure is the one to book if you can: same route, plus complimentary wine and the sunset on the way home.
Zante Mare sends the time within 24 hours. Pickup is at your hotel or at a point within a 5-minute walk of it.
The van drops you by the harbour. Look for two large blue ZANTE MARE flags and two white umbrellas with the logo.
The boat slows to park speed and the crew watch for heads at the surface. When one appears, the code says keep 15 m away and stay quiet.
A 40-minute photo stop through the arches, then 30 minutes to swim in the clear water under the cliffs.
Swim off the sandy beach on Turtle Island. Stay close to the water line: the dry sand holds nests.
A 15-minute photo stop at Cameo Islet, a final 30-minute swim, then back to port and the van to your hotel.
★★★★★The trip was fantastic! Our guide, Stephan, was very helpful and truly skilled [...] we even managed to see some turtles.
★★★★★It was super fun. We made lots of great stops for swimming and also jumped off rocks (about 5 m)!
★★★★★Spearos was a fantastic captain. Took us to all of the best spots and we swam in caves and smiles from start to finish.
★★★★★Dimitris was great, we went to two swim stops and saw one turtle that breached the surface.
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Most trips see at least one, guests report, but nobody can promise it. Loggerheads come up to breathe and then dive, so sightings are often short. Your chances are best from late May to August, when adults gather in the bay to nest.
No. You swim at Keri, on Marathonisi and at one more stop, not next to turtles. ARCHELON asks visitors not to swim with, touch or feed them. Our guide to swimming and turtles explains why.
Agios Sostis harbour, at the western end of Laganas beach. Hotel pickup is included, and the meeting point is marked by two large blue ZANTE MARE flags and two white umbrellas.
The route is the same three hours. The 18:00 departure adds complimentary wine and drinks and puts the sunset on the return leg.
Ready to book
Three hours by speedboat through the marine park: turtle spotting, a swim at the Keri Caves and on Marathonisi, hotel pickup included.
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