Before you book

Seasickness and sea conditions on a Santorini boat tour

9 min read

Most guests on a Santorini boat tour are not seasick. The width between the hulls removes the leaning that alarms people, and the caldera is sheltered by cliffs up to about 300 m. Motion still exists, mostly outside the caldera and after midday. Take tablets before you sail, not once you feel unwell.

This page is for the person reading at midnight, wondering whether to cancel. The short version: the boat is steadier than you are imagining, the caldera is calmer than the open Aegean, and the morning is calmer than the afternoon.

None of that makes motion disappear. So here is where the motion actually is, what helps, and the point at which we would rather you did not book.

What two hulls remove, and what they do not

The fear most people describe is not really sickness. It is the leaning.

A monohull heels. Under sail it leans ten or fifteen degrees and stays there. The deck you are standing on stops being level, and the sea comes up towards one rail. That is the sensation that frightens people.

A catamaran does not do it. Ours is a Lagoon — two hulls held far apart, carrying a flat platform between them. It stays close to level. Nothing tips you towards the water.

What the width does not remove is the up and down. A wave still lifts the boat and sets it down again. On a wide catamaran that motion is quicker and shorter than on a monohull. Some people find quick motion harder, not easier. We would rather say so than sell a level deck as a cure.

The second thing working for you is the caldera itself. It is a flooded collapse basin about 12 km by 7 km, walled on three sides by cliffs up to roughly 300 m. Those cliffs take the north wind off the water. On a windy day the caldera is often the calmest water available anywhere near the island.

The numbers

Where the motion actually is, leg by leg

A five-hour cruise is not five hours of the same sea. Roughly forty minutes of it is exposed and the rest is not.

Leg of the day	What the sea usually does	What it feels like
Out through the south-west gap	The first ten minutes, leaving the shelter of the land	You feel the boat start to work. This is where people decide they are worried.
The south coast: Red Beach to Mesa Pigadia	The exposed stretch. Swell wraps round the corner even on a light day	The part guests notice. It lasts about twenty minutes each way, not two hours.
At anchor at a swim stop	Nearly still. The boat lies head to wind on her anchor	Fine for almost everyone. If you feel wobbly, get in the water — it usually helps.
Round the Akrotiri lighthouse into the caldera	The corner where the sea changes. Sheltered from here on	The relief is physical. Most people notice the boat go quiet under them.
The hot springs at Palea Kameni	Flat. Agios Nikolaos bay is enclosed on three sides	The stillest water of the day, and lunch is served near here for that reason.
The run home past the lighthouse	Inside the caldera the whole way. Wind normally eases towards evening	Cooler than midday and generally calmer. Cliffs on your right the whole way.

The captain reorders the stops when the wind asks him to. On a rough day the sheltered legs get longer and the exposed ones get shorter or disappear. That is the point of letting him decide on the morning rather than printing a fixed route.

Month by month: what the wind does to the sea

Wind, not rain, is what moves the water here. The meltemi is a persistent northerly that dominates the Cyclades in summer. It runs from late May to mid-September, occasionally into October, and peaks from mid-July to mid-August.

Wind descriptions below follow sailingissues.com and greeka.com, both seen 25 August 2026. Sea temperatures are the Climates to Travel monthly averages. This is climatology, not a forecast.

Month	Typical wind	Beaufort when it blows	Sea °C	What that means on a small boat
April	Settling. Northerlies start to organise	Mostly F3–5	16.5	The first workable weeks. Cancellations are still normal, especially early in the month.
May	Mostly settled. Early meltemi episodes are possible	F3–5, occasionally F6	18.5	A good month on the water. The sea is still cold for a long swim.
June	Meltemi establishes from about mid-month, usually weaker than July	Often F4 or less early, F5–6 later	22.0	Generally reliable. The afternoon build is the pattern to watch.
July	Peak meltemi, north to north-west, can blow for days	F4–7, gusting F8	23.5	The windiest operating month with August. A 10:00 start is far more comfortable than 15:00.
August	Peak meltemi. Northerly, near-continuous in some weeks	F4–7, gusting F8	24.5	Warmest water, roughest average afternoons. North-facing coast often unusable.
September	Meltemi weakens. Late in the month it often does not exceed F4	Mostly F4–5 or less	24.0	Frequently the best combination of the year: warm sea, calmer afternoons.
October	Meltemi can still appear. Southerlies return	F3–6, occasionally F7	22.0	Workable but weather-dependent. Keep a spare day in your plans.

Annual context, and the honest baseline: Windfinder's record at Santorini airport, from November 2000 to July 2026, gives a mean of 12 knots from the north-west with mean gusts of 29 knots. This is a windy island by Mediterranean standards. Any single day in August can be flat, and any single day in June can be ugly.

Why the morning is flatter than the afternoon

This is the single most useful thing on the page, and it costs you nothing to act on.

The meltemi has a daily rhythm. It commonly builds through the day and eases in the early evening. Published descriptions put it at Force 4 to 5 by the early afternoon in a normal summer week.

So the sea at 10:00 is not the sea at 15:00. The morning water is flatter, and it is clearer too, because the day's wind has not yet stirred it.

Our day cruise leaves at 10:00 and is back on land at 15:00. The sunset cruise leaves at 15:00, into the windiest part of the day, and comes home in the evening calm. Both are five hours and both cost €100 per person.

If the sea worries you, book the morning cruise. If sunset is the whole reason you are coming, book the sunset cruise and take the tablets seriously.

One more thing about direction. A northerly meltemi leaves the south coast comparatively sheltered. A southerly does the opposite and makes that same coast unworkable while the caldera basin stays flat. Which way the wind blows matters more than how hard.

What helps, and when to do it

This is practical advice, not medical advice. We do not name brands and we do not give doses. Read the label, or ask a pharmacist before you fly.

What	When	Note
Tablets	Before you board, per the label	Most need time to work. Taken after you feel unwell they are much less use. This is the mistake we see most often.
Patches	Per your pharmacist's instruction	Same rule. Ask a professional, not a boat crew, and do it at home rather than in a Fira pharmacy at 08:00.
Ginger, acupressure bands	Any time, including on board	The evidence is mixed. They are cheap and harmless, and some guests are certain they work.
Where to sit	From the moment you step aboard	Aft and low. The cockpit, near the centre line. The bows and the trampolines move most, which is exactly why children love them.
What to look at	Whenever the boat is moving	The horizon, or the island. Not a phone, not a book, not the deck between your feet.
Going below	Avoid it while under way	The cabins below are the worst place on the boat if you are unsettled. Use the heads and come straight back up.
Food	Eat something light before pickup	An empty stomach is worse than a small breakfast. Lunch is cooked on board at the calmest point of the day, which is deliberate.
Alcohol	After the anchor is down, not before	The wine, beer and water are unlimited and included. They will still be there at 13:30.
Telling the crew	The moment you feel it, not an hour later	Two or three crew are aboard. They can move you aft, slow the boat, or run for shelter. None of that is possible if nobody knows.

Nothing on this list is a guarantee. Together they are the difference between a bad twenty minutes and a bad afternoon.

If you are badly affected, a five-hour boat is not the answer

There is a point where none of the advice above helps. If you cannot manage a ferry, if you have been ill on a small boat before, if the thought of it is already spoiling the week — do not book a five-hour cruise.

We would rather tell you now than take your money and watch you have a bad afternoon in front of fourteen other people. There is no version of that day we can rescue once the anchor is up.

Message us on https://wa.me/306989771888 and say plainly how bad it is. If the honest answer is no, you will get it.

There are other ways to see this coastline. The rim walk from Fira to Oia. A table at Ammoudi at the water's edge. Or the RIB, which is private and priced per route, so a short run is possible where five hours is not.

Ready when you are

Tell us you are worried about the sea

Send your dates and say how you are with boats. We will tell you what the wind normally does that week, and whether the 10:00 departure is the one to take. If we think the day will not suit you, we will say that instead.

Check availability & book

Call the harbour office+30 698 977 1888

Common questions

Will I get seasick?

Most guests do not. Two hulls held wide apart make the boat far steadier than a monohull, and the caldera is sheltered by cliffs up to about 300 m. If you are prone to motion sickness, take medication before boarding rather than waiting for symptoms, and stay on deck watching the horizon.

How rough is the water?

Inside the caldera the cliffs block most of the wind and the water is usually calm. Outside it, along the south and west coasts, it gets choppier, especially in the afternoon once the meltemi has built. Mornings are the flatter sailing, which is why our day cruise leaves at 10:00.

Is a catamaran better than a monohull if you get seasick?

For most people, yes. A catamaran does not heel, so the deck stays close to level and nothing leans you towards the water. It still rises and falls with the swell, and that motion is quicker and shorter than a monohull's. A few people find quick motion harder rather than easier.

Is the morning or the afternoon calmer in Santorini?

The morning, in almost every summer week. The meltemi builds through the day and eases in the early evening, so the sea at 10:00 is flatter and clearer than the sea at 15:00. If the water worries you, book the day cruise rather than the sunset one.

Where should I sit to avoid seasickness?

Aft and low, in the cockpit and near the centre line, where the boat moves least. Look at the horizon or at the island, not at a phone. Stay on deck rather than going below. The trampolines forward are the liveliest place aboard, which is why children head straight for them.

What happens if I feel sick during the cruise?

Tell the crew immediately. Two or three of them are on board and they deal with this regularly. They can move you aft, slow the boat down, or run for the sheltered side of the island. The one thing that does not help is sitting quietly hoping it passes.

Will I be able to join a catamaran cruise if I get easily seasick and cannot swim?

Often yes on both counts. Swimming is entirely optional and several guests on any cruise never get in. For the seasickness, be honest with us before you book. If you are badly affected rather than mildly, we will tell you the day is not worth your money.

Santorini Boat Tour - Water Taxi is a catamaran cruise and water taxi operator based in Fira, Santorini.

Updated August 2026