Ostria

Ostria sits directly on the harbour at Merihas, Kythnos's main port village, which means the boats unloading the morning catch are practically within arm's reach of the kitchen. The restaurant has been part of the Merihas seafront since 1997 — its Instagram handle makes the founding year plain — and with 758 Google reviews averaging 4.4 stars it has a well-established reputation among both island regulars and visitors stepping off the ferry.

Merihas is where most travellers arrive on Kythnos, and Ostria is one of the first things you see when you walk off the dock. That position is not accidental: the restaurant makes the most of its setting, with tables arranged so that the view of the small protected bay is a constant presence throughout the meal. The menu centres on what the Cyclades have always done best — grilled fish, seafood plates, and straightforward Greek taverna cooking.

Kythnos is one of the quieter Cycladic islands, without the cruise-ship crowds of Mykonos or Santorini, and Ostria reflects that character. The pace here is unhurried, portions are generous by Greek island standards, and the clientele on any given evening will include Greek families from Athens on weekend breaks alongside the occasional foreign traveller who has made a point of seeking out the less-visited islands.

What to Expect

Ostria operates as a full-service seafood and Greek cuisine restaurant, the kind of place where the menu follows what is fresh rather than a fixed printed card. Expect the classics of the Cycladic table: grilled whole fish priced by weight, octopus, fried squid (kalamari), shrimp saganaki, and the cold mezedes — taramosalata, tzatziki, fava — that precede a main course in any serious Greek meal. Meat options are typically present for those who prefer them, including grilled chops and the ubiquitous souvlaki, but fish and seafood are the reason most people sit down here.

The physical space is waterside, with outdoor seating directly facing the harbour. Merihas bay is sheltered, so even when the meltemi wind picks up across the broader Aegean, conditions at the table remain comfortable. Inside seating is also available. The atmosphere shifts across the day: lunch service tends to be relaxed and family-oriented, while evening tables fill up with diners who have spent the day at nearby beaches like Episkopi or Apokrousi and are ready for a proper sit-down meal.

Service is in the Greek taverna tradition — attentive without being formal, and knowledgeable about the day's fish. If you want to know what came in that morning, ask; it's a normal part of ordering at this kind of restaurant. The Facebook page categorises it at the mid-price range ($), which is consistent with the standard of waterfront seafood tavernas on Cycladic port villages.

How to Get There

Ostria is in Merihas, Kythnos's ferry port, at the address Merihas 840 06. From the ferry terminal, the restaurant is a short walk along the harbour front — you will see it as you disembark. If you are coming from Driopida (the medieval capital inland) or Chora (the main town to the north), you will need a car, taxi, or the island's bus service, which connects these villages to Merihas. The drive from Chora takes roughly 10 to 15 minutes on the main island road.

Parking is available along the Merihas waterfront road, though it fills up on summer weekends when day-trippers and ferry passengers arrive simultaneously. If you are staying elsewhere on the island, arriving by scooter or rental car is the most flexible option. There is no boat access specific to the restaurant itself, but the ferry from Lavrio (Attica) docks in Merihas, making this an easy first or last meal on the island.

Best Time to Visit

Ostria is open year-round, or close to it — the listed hours reflect essentially all-day trading. Kythnos has a longer shoulder season than the more tourist-dependent Cycladic islands because it draws Greek visitors who come for the thermal springs at Loutra and weekend escapes from Athens, so you will find the restaurant operating well into October and potentially open in spring from late March or April.

For the best experience, aim for an evening table between late June and early September when the harbour is at its most active. Sunset falls over the western side of the island and the light across Merihas bay in the early evening is worth timing your meal around. Midday in July and August can be very hot; a long lunch with wine and shade works well, but the evening sitting is cooler and more atmospheric. Weekends throughout summer are busier, with Athenians arriving on Friday and Saturday ferries — if you prefer a quieter meal, a weekday evening is the better choice.

Tips for Visiting

• Book ahead in high summer. Merihas is a small village but Ostria draws consistent custom; on July and August weekends, turning up without a reservation risks a long wait for a harbour-view table. Call +30 2281 033017 to reserve.
• Ask what fish came in that day. The server will tell you what is freshest; this is the most reliable way to order well at any Greek harbour taverna. Fish is typically priced by weight — confirm the weight before it goes to the grill.
• Arrive on the early ferry and eat lunch here. The Lavrio–Kythnos ferry arrives in Merihas, and Ostria is steps from the dock. A lunch before heading to your accommodation is a practical and enjoyable way to start the trip.
• Order at least one cold meze to start. Fava (split-pea purée) is a Cycladic speciality and a reliable indicator of kitchen quality at any island taverna.
• Allow for a long meal. Greek taverna dining is not quick by design. Budget 90 minutes to two hours for a full lunch or dinner, especially in the evening.
• The harbour-side tables fill first. If a specific table matters to you — right on the water rather than one row back — mention it when you call to reserve.
• Check the Facebook and Instagram pages before visiting out of season. The restaurant has been operating since 1997 and is well-established, but shoulder-season hours can vary. The social media accounts are the fastest way to confirm current status: facebook.com/ostriarestaurantkythnos and @ostria_restaurant_kythnos1997 on Instagram.
• Combine with the nearby beaches. Merihas beach is immediately north of the port. Episkopi and Apokrousi beaches are a short drive away. An afternoon at one of these followed by dinner at Ostria is a natural day structure on Kythnos.

What to Order

Fresh grilled fish is the main event at Ostria, as it is at most serious Cycladic waterfront tavernas. Whole fish — bream (tsipoura), sea bass (lavraki), red mullet (barbounia) — grilled simply with olive oil, lemon, and fresh herbs is the benchmark dish. Octopus prepared on the grill (htapodi scharas) or as a vinegar-dressed salad (htapodi xydato) is worth ordering if it is on offer; it is a Greek harbour staple and Ostria's waterfront credentials make it the right place to eat it.

For a full meal, start with a spread of cold mezedes: taramosalata, tzatziki, a Greek salad (horiatiki) with local tomatoes and proper barrel feta, and perhaps a plate of grilled bread (psomi scharas) to work through while you decide on mains. Shrimp saganaki — prawns cooked in a tomato and feta sauce — is a Cycladic favourite and a reliable choice if you want something more substantial than grilled whole fish. Fried kalamari is a crowd-pleasing option and pairs well with a cold Mythos or a glass of crisp Assyrtiko, the white wine grape native to the southern Cyclades.

For dessert, Greek tavernas typically offer simple options — watermelon in summer, a slice of galaktoboureko (custard pastry), or fruit. Do not expect an elaborate pastry menu; the focus here is on the savoury courses.