The Santorini hot springs are the most oversold and most misunderstood item on the island’s excursion menu, and we would rather tell you plainly what they are before you book. They are not a spa, there are no pools, no changing rooms and no path from a beach. They are a shallow bay on a volcanic islet where warm sulphurous water seeps out of the seabed, stains the sea rust-orange, and is reached by jumping off a boat and swimming a hundred metres. Understood on those terms it is a genuinely memorable twenty minutes. Expecting anything else leads to disappointment, which is why our Santorini Tours team explains it before guests get on the boat.
The springs sit at Agios Nikolaos on Palea Kameni, the older of the two black islets in the middle of the caldera. Almost everybody reaches them on the standard volcano cruise, which climbs the crater on Nea Kameni first and then anchors here.
The Short Answer
They are warm, not hot. Somewhere around thirty to thirty-five degrees at the vents and cooler within a few metres.
You swim to them. Boats anchor fifty to a hundred metres out, and you get in off the back of the vessel.
The water is orange with iron oxide, and it will permanently stain light swimwear.
You get fifteen to thirty minutes, set by the boat schedule.
Worth doing once, as part of the volcano trip, and not a reason to book on its own.
The Caldera the Springs Sit In
Santorini Hot Springs at a Glance
| Detail | Reality | Notes | Watch for |
|---|---|---|---|
| Where | Palea Kameni, the older volcanic islet | A shallow bay called Agios Nikolaos | About 20 minutes by boat from the old port |
| Temperature | Warm rather than hot | Roughly 30 to 35C at the vent, cooler further out | Nothing like a thermal spa |
| How you get in | You swim | Boats anchor 50 to 100 metres out | There is no jetty and no ladder to the shore |
| The water | Rust-orange from iron oxide | Sulphurous, with a distinct smell | It stains light swimwear permanently |
| The bottom | Volcanic rock and mud | Uneven and sharp in places | Water shoes help |
| How long | 15 to 30 minutes | Set by the boat, not by you | Part of a longer excursion |
| Cost | Included | Within the volcano and hot springs cruise | Rarely sold separately |
| Best time | Morning sailings | Calmer water and fewer boats | Afternoons get crowded and windy |
| Who it suits | Confident swimmers | Open water, a real swim from the boat | Not for weak swimmers or small children |
| Verdict | Worth doing once | An odd, memorable twenty minutes | Not the reason to book the cruise |
Read the temperature row and the swimwear row together and you have the two facts that surprise most visitors to the Santorini hot springs.
What the Santorini Hot Springs Swim Is Actually Like
The boat anchors offshore. Fifty to a hundred metres from the bay, because the water inside is too shallow and the bottom too rocky for a vessel that size.
You get in off the back. A ladder or a platform, and then open water.
The first stretch is cold. Caldera water is deep and properly cool, and this is the part nobody mentions in the brochure.
Then it warms. As you approach the bay the temperature climbs in patches rather than evenly, and the colour changes from blue to a milky rust.
The warmest water sits right against the rock at the head of the bay, and even there it is bath-warm at best rather than hot.
The bottom is volcanic mud over rock, uneven and sharp in places, so standing is not always comfortable.
The smell. Sulphur, unmistakable, and stronger on a still day.
How long you get. Fifteen to thirty minutes, decided by the boat rather than by you.
Getting back is the same swim in reverse, against whatever current is running. This is the part that catches out weaker swimmers at the Santorini hot springs, and it is the reason we ask guests to be honest about their swimming before they jump in.
The Orange Water and Your Swimwear
The colour is iron oxide. Groundwater heated by the volcano dissolves iron from the rock and precipitates it when it meets the sea.
It stains. Permanently, in our experience, on white and pale fabrics.
Wear something dark or something you do not mind losing. This is the single most useful piece of advice about the Santorini hot springs and the one most often given too late.
Rinse immediately afterwards; most boats have a freshwater hose.
Jewellery. Silver tarnishes in sulphurous water. Leave it on the boat.
Is it good for the skin? The claim is traditional rather than tested. The minerals are real and the therapeutic effect is folklore. Enjoy it as an oddity, not a treatment.
The Volcano Trip It Belongs To
The springs are one stop on a standard excursion, and the rest of it is arguably better.
Nea Kameni. The younger black islet, where you land and walk up to the crater rim on a gravel path. Thirty to forty-five minutes up, with steam vents and a genuinely lunar landscape at the top.
Palea Kameni. The older islet, where the Santorini hot springs are.
Thirassia. Many full-day versions continue to the island across the caldera for lunch. See our Thirassia guide.
Sunset return. The full-day trips come back past Oia at the end of the afternoon.
Where it leaves from. The old port below Fira, reached by cable car, on foot down 588 steps, or by donkey, which we ask you not to use.
How long. Half a day for volcano and springs, a full day with Thirassia and the sunset.
Our volcano tour guide covers the whole excursion in detail.
Who Should Swim at the Santorini Hot Springs
Confident swimmers. The Santorini hot springs are a real open-water swim of fifty to a hundred metres each way, in deep cool water before you reach the warm bay.
Weak swimmers. Stay on the boat, or wear a buoyancy aid if the crew offers one. Every season people get into difficulty here because the swim looked shorter from the deck.
Small children. We would not. There is no shallow entry, no shore to stand on and no lifeguard.
Older travellers. Fine if you swim regularly, and the ladder back onto the boat is the hard part rather than the swim.
Anyone with skin conditions. Sulphur and iron are strong; if in doubt, do not.
Anyone who dislikes cold water. The first thirty metres are genuinely cold, and a surprising number of people turn back at that point.
Photographers. Leave the camera on the boat, or bring something genuinely waterproof.
When to Visit the Santorini Hot Springs
Morning sailings are calmer, less crowded and better lit.
Afternoon sailings hit the springs when the wind has built and half a dozen boats are anchored in the same bay.
June and September are the best months: warm air, warm sea and manageable crowds.
July and August are the busiest, and on a peak day the bay at the Santorini hot springs holds several hundred swimmers at once.
April, May and October are quieter, and the caldera water is cold enough that the contrast is sharper.
Winter. No scheduled boats. The excursion does not run.
Windy days. Trips are cancelled outright rather than shortened, because the anchorage is exposed. See our weather guide.
What to Bring
Dark swimwear you are prepared to lose.
A towel, because most boats do not provide one.
Water shoes, which make the rocky bottom far more comfortable.
Sun protection, since there is no shade at anchor and you will be on deck for hours.
Water and a snack, as on-board catering is limited and expensive.
A dry bag for a phone.
Shoes with grip for the crater walk on Nea Kameni, which is gravel and considerably harder work than the springs.
Cash, for the small entry fee at the volcano and for drinks on board.
Why the Santorini Hot Springs Are Warm
The volcano is active. Not erupting, but alive: the caldera is a functioning volcanic system with a magma chamber beneath it.
Seawater seeps into the rock, is heated at depth, and rises again through fractures.
It carries minerals with it. Iron, sulphur and manganese, which is what gives the Santorini hot springs their colour and their smell.
The iron oxidises on contact with oxygenated seawater and precipitates as the rust-coloured cloud you swim through.
Palea Kameni emerged from the sea around two thousand years ago; Nea Kameni is younger still, built up by eruptions between the sixteenth and twentieth centuries.
The last eruption here was in 1950, which is recent enough that the ground on Nea Kameni is still warm in places.
Is it safe? Yes. The volcano is monitored continuously and the springs themselves are simply warm mineral water.
Our Akrotiri guide covers what the same volcano did three and a half thousand years ago.
If You Do Not Want to Swim
Stay on the boat. Plenty of people do, and the view of the bay from the deck is the same colour.
Do the volcano and skip the springs. Some half-day trips are volcano-only, and the crater walk is the better half anyway.
Take a sailing or catamaran cruise instead. These swim at the red and white beaches on the south coast, where the water is clear and the entry easier.
Swim from a beach. Perissa, Perivolos and Kamari are all straightforward, and Monolithos is shallow and calm.
Be honest with yourself. The Santorini hot springs are a novelty, not a highlight, and nobody should feel obliged to make a hundred metre swim to tick them off.
Our Honest Verdict
Worth doing once, if you swim confidently and the day is calm.
Not worth booking a trip for on its own. The volcano crater, Thirassia and the sunset return are the substance of the excursion.
Do not expect a spa. There is no infrastructure of any kind at the Santorini hot springs, and that is part of the appeal for some visitors and a genuine disappointment for others.
Manage the group. If half your party will not swim, choose a trip where the boat time ashore matters more.
What people remember. Usually the colour of the water and the smell, rather than the warmth.
What people regret. White swimwear, every single time.
Choosing the Right Boat
Large excursion boats. Cheapest, busiest, and they anchor furthest out. The swim to the Santorini hot springs is longest from these.
Traditional wooden boats. Smaller groups, more character, and generally a shorter swim.
Catamarans. The most comfortable, with fewer passengers, food on board and a swim platform. They usually visit the springs as one stop among several.
Private charter. You choose the timing, which means arriving before or after the crowd.
Half day or full day. Half day covers volcano and springs; full day adds Thirassia and often the sunset.
What to ask before booking. How long at the springs, how far the boat anchors, whether a buoyancy aid is available, and whether there is a freshwater rinse on board.
Getting to the boat. Almost all leave from the old port below Fira. Allow time for the cable car queue, which is long at peak. See our port guide.
Santorini Hot Springs: Common Questions
How hot are the Santorini hot springs?
Warm rather than hot, roughly thirty to thirty-five degrees at the vents and cooler within a few metres. Nothing like a thermal spa.
Where are they?
At Agios Nikolaos bay on Palea Kameni, one of the two volcanic islets in the middle of the caldera, about twenty minutes by boat from the old port below Fira.
Do you have to swim to them?
Yes. Boats anchor fifty to a hundred metres out and you swim in from the vessel. There is no jetty and no shore access.
Will the water stain my swimsuit?
Yes, permanently on light fabrics. Wear something dark or something you do not mind losing.
How long do you get?
Fifteen to thirty minutes, set by the boat rather than by you.
Are they suitable for children?
Not really. There is no shallow entry, no shore and no lifeguard, and the swim is in open water.
Do the springs smell?
Yes, of sulphur, and more strongly on a still day.
Are they good for your skin?
The claim is traditional rather than proven. Treat it as an oddity rather than a treatment.
Can you visit the Santorini hot springs without a tour?
Not practically. There is no scheduled service to Palea Kameni, so you go on an excursion or a private charter.
Is it worth it?
Once, as part of the volcano trip, if you swim confidently. It is not a reason to book the cruise on its own.
What is the best time of day?
Morning, when the water is calmer and fewer boats are anchored in the bay.
Do trips run in winter?
No. The excursion is seasonal, roughly April to October.
Santorini Hot Springs: Key Points
- The Santorini hot springs are at Agios Nikolaos bay on Palea Kameni.
- They are warm rather than hot, around thirty to thirty-five degrees at the vents.
- You reach them by swimming fifty to a hundred metres from an anchored boat.
- The first stretch of that swim is cold, deep caldera water.
- The rust colour is iron oxide and it stains light swimwear permanently.
- The smell is sulphur and it is stronger on still days.
- You get fifteen to thirty minutes, decided by the boat.
- There is no jetty, no changing room and no lifeguard.
- Morning sailings are calmer and less crowded.
- Trips run roughly April to October and are cancelled in strong wind.
- The crater walk on Nea Kameni is the better half of the excursion.
- Weak swimmers and small children should stay on the boat.
The Excursion, Hour by Hour
10:00. Cable car down from Fira to the old port, or the walk down the steps.
10:30. Board and sail out into the caldera.
11:00. Land on Nea Kameni and climb to the crater rim, thirty to forty-five minutes up through black gravel and steam vents.
12:30. Back aboard and a short hop to Palea Kameni.
13:00. Anchor off the bay. The Santorini hot springs swim, fifteen to thirty minutes.
13:45. Sail on to Thirassia on a full-day trip, or back to Fira on a half day.
15:00. Lunch in Manolas above Korfos, on the full-day version.
17:30. Sail back past Oia for the sunset if the trip includes it.
19:30. Back at the old port, and the cable car queue at its worst.
Our three day itinerary shows where this fits in a short trip.
Mistakes People Make at the Santorini Hot Springs
White swimwear. Every boat, every day.
Overestimating the swim. It looks shorter from the deck than it is in the water.
Expecting a spa. There is nothing built at the Santorini hot springs at all.
Expecting hot water. It is warm, and only in patches.
Wearing silver. Sulphur tarnishes it.
Leaving a phone in a pocket. There is nowhere dry to put anything once you are in.
Booking an afternoon boat when a morning one was available.
Skipping the crater to save energy for the springs, which is the wrong way round.
Wearing sandals for Nea Kameni. The gravel path punishes them.
Cutting the cable car queue too fine on the way back.
Quick Answers on the Santorini Hot Springs
How hot are the Santorini hot springs? Warm, around thirty to thirty-five degrees at the vents.
Where are the Santorini hot springs? Agios Nikolaos bay on Palea Kameni.
How do you reach them? By swimming in from an anchored boat offshore.
How far is the swim? Fifty to a hundred metres in each direction.
How long ashore? There is no ashore at all; fifteen to thirty minutes in the water.
Colour? Rust-orange, from dissolved iron oxide.
Smell? Sulphur, stronger on a still day.
Will it stain? Yes, permanently, so wear dark swimwear to the Santorini hot springs.
Children? Not recommended for young ones.
Season? The Santorini hot springs boats run roughly April to October.
Worth it? The Santorini hot springs are worth doing once, as part of the volcano trip.
How It Compares With the Rest of the Trip
The crater walk on Nea Kameni is the highlight for most people: a genuinely lunar landscape, steam vents, and a view back at the caldera wall.
The Santorini hot springs are the novelty: twenty minutes of warm orange water and a story to tell.
Thirassia is the calm: a clifftop village, a long lunch and no crowds.
The sunset return is the beauty: the caldera wall from the water with the light going.
If you had to drop one, drop the springs. If you had to keep one, keep the crater.
If you cannot swim well, the trip is still worth taking for the other three.
The Crowds, and How to Miss Them
Every boat goes to the same bay. There is one anchorage and one set of vents, so at peak times a dozen vessels sit in a line off Agios Nikolaos.
The water gets busy rather than dirty. It is a large bay, and it still feels crowded when two hundred people are swimming in it.
The first morning boats often have the Santorini hot springs almost to themselves.
Private charters can time the visit for late afternoon after the big boats leave.
Catamaran cruises tend to arrive between the peaks.
What we would book. A morning departure in June or September, which is the quietest realistic combination.
What to avoid. A midday boat in August, when the bay is at its fullest and the wind is building.
Safety, Plainly
It is open water. Deep, cool and occasionally with a current running across the mouth of the bay.
There is no lifeguard and no shore to stand on for most of the swim.
Crews watch from the boat, and on a busy day they are watching a hundred people at once.
Ask for a buoyancy aid if you are at all unsure; most boats carry them and nobody minds.
Do not swim alone to the far side of the bay.
Get out if you are cold. The swim back is longer than the swim out feels.
Alcohol. Some boats serve it before the swim. We would not.
The honest summary. The Santorini hot springs are safe for competent swimmers on a calm day and genuinely risky for anyone who overestimates themselves.
The Islets Themselves
Palea Kameni means “old burnt one”. It rose out of the caldera around AD 46 and has been quiet since the seventeenth century. The Santorini hot springs are on its northern shore, beside a small white chapel dedicated to Agios Nikolaos.
Nea Kameni means “new burnt one” and is younger again, built up by eruptions between 1570 and 1950. It is the one you climb.
The chapel at the springs is tiny, whitewashed and usually locked, and it is the only building on that side of the islet.
Nothing grows there. Both islets are bare black rock with a few hardy plants, which is why the landscape feels so unlike the rest of Greece.
The caldera around them is up to four hundred metres deep, which is why cruise ships anchor rather than dock.
Monitoring. The volcano is watched continuously by the institute that studies it.
Why this matters to a swimmer. The warmth under you at the Santorini hot springs is not a curiosity bolted onto a boat trip; it is the volcano itself, still working.
Photographing It
The colour is the shot. The boundary where blue caldera water meets rust-orange spring water is sharp and strange.
Shoot from the boat before you get in, from the upper deck if there is one.
Morning light is better and the water is calmer.
Waterproof cameras only in the water; there is nowhere dry once you are swimming.
Include the chapel for scale against the black rock.
From the crater rim on Nea Kameni you can see the stain in the bay across the channel, which is the best overall view of the Santorini hot springs.
Going as a Family
The boat trip works for children; the swim frequently does not.
Nea Kameni is a hot gravel climb, manageable for children who walk well and hard work for small ones.
The Santorini hot springs swim is open water with no shallow entry, so most families keep younger children on board.
Older children who swim confidently usually love it, and the orange water is the part they remember.
Bring more water than you think, because there is no shade at anchor.
Consider a half day rather than the full trip with children, since the sunset return makes for a very long afternoon.
See our family tours and our large families guide.
The Short Version
The Santorini hot springs are a warm, sulphurous, rust-orange bay on a volcanic islet, reached by a hundred metre swim from an anchored boat, for fifteen to thirty minutes, as one stop on the volcano excursion.
Wear dark swimwear, take a morning sailing, and go in with the right expectation: this is a strange and memorable dip in a working volcano, not a spa. On that basis it is worth doing once, and the crater walk that comes before it is worth doing regardless.
Beliefs Worth Correcting
“There are pools.” There are not. The Santorini hot springs are open sea in a bay, with no built structure of any kind.
“You can walk in from a beach.” You cannot. There is no road, no path and no landing point for visitors.
“It is hot.” It is warm, in patches, and cooler than most people’s bath.
“It cures things.” The mineral content is real; the medical claims are folklore.
“The stain washes out.” On light fabrics it generally does not.
“You can visit independently.” Only by private charter; there is no scheduled service.
“It is the best part of the cruise.” For most of our guests it is the crater walk, and the Santorini hot springs come second or third.
“The trip runs year round.” It does not; the season is roughly April to October.
Everything in One Paragraph
The Santorini hot springs are a shallow, sulphurous, iron-stained bay at Agios Nikolaos on the volcanic islet of Palea Kameni, about twenty minutes by boat from the old port below Fira, visited as one stop on the standard volcano excursion between roughly April and October. Boats anchor fifty to a hundred metres offshore and you swim in through cold caldera water to reach patches that are warm rather than hot, spend fifteen to thirty minutes there, and swim back. Wear dark swimwear because the iron stains permanently, take a morning sailing for calmer water and fewer boats, and treat the whole thing as a memorable curiosity rather than as a spa.
What It Costs
The springs themselves are free. There is no ticket and nobody to sell one; access to the Santorini hot springs is included in whatever boat you are on.
The excursion is the cost. A half-day volcano and springs trip is modest; a full day with Thirassia and the sunset costs more.
Nea Kameni has a small entry fee paid on landing, usually in cash.
Catamaran cruises cost several times the basic boat and include food, drink and far fewer passengers.
Private charters are the most expensive and the only way to control the timing.
The cable car down to the old port is charged separately each way.
Value for money. The basic volcano trip is one of the cheapest half days on the island, and on that basis the Santorini hot springs are good value even if the swim disappoints.
One Line to Take Away
Book a morning volcano boat, wear dark swimwear, and treat the Santorini hot springs as a strange twenty minute swim in a working volcano rather than as a spa.
Everyone who goes in with that expectation enjoys it. Everyone who goes in expecting warm pools and a changing room does not, and the difference costs nothing but knowing beforehand. The crater walk that precedes the Santorini hot springs is the part most of our guests talk about afterwards, and it asks nothing of your swimming at all.
What Else Is Nearby
Nea Kameni crater, ten minutes away by boat and the other half of the same excursion.
Thirassia, across the caldera, for lunch on a clifftop.
Ammoudi Bay, below Oia, for fish tavernas and swimming off the rocks.
The old port below Fira, where the boats leave and the cable car lands.
Red Beach and White Beach, on the south coast, reached by small boat from Akrotiri and easier to swim at than the Santorini hot springs.
The rim path, free and above all of it, from Fira to Imerovigli.
Booking With Us
We do not operate the boats, and we will tell you honestly which version of the trip suits your group and get you to the port in time for it. Per vehicle rather than per person, no deposit, free cancellation.
Tours
- full day tour
- half day tour
- north part and Oia tour
- south part and Akrotiri tour
- sightseeing tour
- historical tour
- wine tour
- food experience
- sunset tour
- shore excursion
- small group tour
- black sand beach tour
- horse riding tour
- custom tour
- coach tours
Transfers
- island transfers
- VIP chauffeur service
- transfer to Oia and Finikia
- transfer to Fira and the villages
- choosing a private transfer
Book directly
- Full Day Tour
- Half Day Tour
- North Part and Oia Tour
- South Part and Akrotiri Tour
- Sightseeing Tour
- Small Group Tour
- Wine Tour
- Food Experience
- Historical Tour
- Sunset Tour
- Shore Excursion
- Black Sand Beach Tour
- Horse Riding Tour
- Personalised Tour
Further reading
- The volcano tour explained
- Thirassia, across the caldera
- Akrotiri
- Santorini museums
- Things to do in Santorini
- A three day itinerary
- The best beaches
- Santorini weather and the meltemi
- The cruise port explained
- Where to stay in Santorini
- Santorini to Ios
- Santorini to Naxos
- Santorini to Paros
- Santorini to Mykonos
- Santorini ferry tickets
- Santorini airport
- Day trips from Santorini
- Santorini hiking
- Santorini in winter
- Why we ask you not to ride the donkeys
More from this site
- All tours and prices
- About Santorini Impressive Tours
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- Pictures from our private tours
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- All our Santorini articles
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