Marathonisi (Turtle Island) and Keri caves

The boat trip and what it costs

Marathonisi, nicknamed Turtle Island for its shape and its loggerheads, sits in Laganas Bay — a protected national marine park on Zakynthos’s southern coast. The easy way to see it is a boat from Keri or Laganas, where small glass-bottom and eco boats pair turtle-spotting in the bay with a stop at the islet’s pale crescent beach and a run along the Keri sea caves. Trips start from roughly €25 per adult, with children cheaper; longer or private outings cost more, and prices shift with operator and season.

The big draw is that you skip the long, winding drive north to the Navagio viewpoint. From the southern resorts the whole thing is close to hand, so it suits families and anyone who’d rather have a relaxed half-day on the water than a full coach excursion.

Turtles, timing and honest expectations

Aim for a morning departure. The sea is calmest then, and loggerheads surface to breathe in flat water, so they’re far easier to spot near the boat. That said, these are wild animals in a protected reserve — sightings are likely but never guaranteed, and a good operator keeps a respectful distance rather than chasing them.

Allow two to four hours depending on the trip. Choose a smaller eco or glass-bottom boat over the big party vessels: you’ll get closer to the wildlife with less noise, and the marine-park rules are taken more seriously. Sailings are weather-dependent, so check the day before.

Is it worth it? For the south of the island, yes. It’s a gentler, wildlife-led counterpart to the dramatic Shipwreck day, and the Keri caves are genuinely lovely in clear light. Keep it realistic, though — Laganas Bay is busy in peak summer, and the beach stop on Marathonisi can get crowded. Confirm current times and prices with your chosen operator before you book.