Santorini: Boat tour to Volcano, Hot Springs & Thirasia island

Santorini’s caldera is best understood from the water, where black volcanic islands, steep cliffs, and warm sulfur springs tell the story of the eruption that shaped the region. This half-day trip combines a volcano walk with a swim at Palea Kameni and free time on quieter Thirassia.

I like the small-group format, capped at 24 people, and the chance to visit Thirassia for lunch instead of spending the whole morning around Santorini’s busiest ports. The boat also provides towels, water, pool noodles, and a glass of local wine. The main drawback is pace: delays can shorten the hot-spring swim or Thirassia stop, and the volcano hike has little shade.

Key points to know before booking

• The volcano hike is self-guided: You walk across rough black volcanic ground to the crater on your own, with no guide beside you.
• The hot springs require swimming: The water is warm rather than hot, and the swim from the boat is deep enough that you should be comfortable in open water.
• Thirassia gives you a quieter Santorini: You have free time for the village of Manolas, waterfront food, and a slower island feel.
• The group stays relatively small: With a maximum of 24 people, boarding and moving between stops should feel more personal than on a large excursion boat.
• Bring cash for two extra costs: The cable car is €10 each way, and entry to Nea Kameni costs €5 per person.
• Pack for wind and sulfur: Light-colored swimwear may stain, while a sweatshirt or windbreaker helps on the open water.

Why this boat trip is different from a standard Santorini outing

Many Santorini excursions focus on sunsets, beach time, or a quick cruise beneath the cliffs. This one is about the caldera’s volcanic story. In roughly five hours, you visit the active volcanic island of Nea Kameni, stop at the sulfur waters of Palea Kameni, and then see a quieter side of the old Santorini on Thirassia.

I like that the day has three distinct parts. You get a short hike, a swim, and time to eat or wander. No single activity lasts long enough to dominate the whole trip, though that also means you need to watch the clock.

The boat carries up to 24 people and has a restroom, foam pool noodles, towels, and bottled water. The setup is practical rather than luxurious. You should expect a pleasant traditional boat outing, not a private yacht charter. The crew has included captains Panagiotis and Manos, both praised for being kind and helpful, and the captain’s skill matters when the water turns choppy.

The tour begins at 10:15 a.m. at Santorini Old Harbor, also called Fira Port. It finishes at the same place. You can use the mobile ticket, but the trip still requires some planning because the harbor sits below Fira.

Getting down to Santorini Old Harbor

The Old Harbor lies beneath Fira’s cliffs. You can reach it by cable car, on foot via the steps, or by traditional donkey. For most people, the cable car is the practical choice, especially before a boat trip and in the heat of summer.

Budget €10 each way for the cable car. That cost is not part of the $83 tour price, so two cable-car rides add €20 per person. You also need €5 in cash for Nea Kameni. Bring those fees with you rather than counting on a card at every point of the morning.

The port itself has waterfront tavernas, shops, and cafés. Give yourself enough time to get down, since the cable car can be busy and the meeting point is at sea level. The tour returns here after the boat ride, so you will need to make the climb back to Fira at the end.

Sailing across the caldera to Nea Kameni

The first sailing takes about 20 minutes. This is when Santorini’s shape makes the most sense. From the water, the cliffs rise sharply toward the white villages above, while the dark volcanic rock around the caldera shows how different this part of the Aegean is from a typical sandy island.

Nea Kameni is a small volcanic island with a stark surface of black and brown lava rock. The walk takes about 1 hour and 15 minutes, including time to reach the crater area and look around. The trail is not presented as a guided hike. You are responsible for your own pace and safety.

That detail matters. You should wear firm shoes, carry water, and avoid treating this as a casual stroll in sandals. The ground is uneven, and the August heat can make even a moderate uphill walk feel hard. There is little reason to rush, but you must return to the boat on time.

The €5 admission fee is separate. You will see rough volcanic ground and crater views rather than a developed visitor site. That simplicity is part of the appeal. You are not walking through a museum or along a paved promenade. You are moving across an exposed volcanic island with wide views back toward Santorini.

I like this stop because it gives the rest of the trip context. After seeing Nea Kameni, the dark rock, sulfur water, and steep caldera walls are not just pretty scenery. They become pieces of the same geological story.

Swimming at Palea Kameni’s sulfur springs

From Nea Kameni, the boat continues to Palea Kameni. The stop lasts about 30 minutes, though the actual time in the water can be shorter if boarding takes a while or the schedule slips.

The springs contain sulfur, iron, and other volcanic minerals. The water is described as warm, but do not picture a steaming spa pool. Conditions change, and the spring area can feel only moderately warm. One important practical point is that you normally swim from the boat to the warm water, rather than stepping onto a broad beach.

The water is deep, and you need to keep swimming. Pool noodles are supplied, which helps you float and rest, but they do not replace basic swimming ability. If you are not a confident swimmer, this may be the least comfortable part of the trip. A child who cannot swim well may not be able to use the springs.

Wear an old or dark swimsuit. Sulfur can stain light-colored fabric. The boat provides a towel, and you should return it to the staff rather than pack one from your hotel. You also receive a bottle of water, which is useful after the volcano walk and swim.

The hot-spring stop is one of the tour’s most memorable features, but it is also the part most sensitive to timing. If the group leaves late, a 30-minute swim can shrink considerably. Boarding one person at a time takes effort, so stay close to the boat when the captain gives the return signal.

A slower hour on Thirassia

Thirassia is the trip’s best counterpoint to the volcanic stops. The island was once connected to Santorini before the huge eruption in the 16th century BC. Today, it feels much less developed than Fira or Oia.

You have about 1 hour and 15 minutes here in the planned schedule. Use it for a short walk through the lanes of Manolas, the main village, or sit at a traditional waterfront taverna for lunch. The stop is not a formal guided tour, so you decide how to spend the time.

This is where the tour feels most local and relaxed. Thirassia’s Cycladic houses and quiet lanes offer a useful contrast to Santorini’s packed streets. If you want a full village tour, an extended meal, or a long hike, the time may feel tight. If you simply want a calm lunch with a view and a look at traditional island life, it works well.

Plan your meal carefully. Restaurant service can take much of the available hour, especially if the boat arrives late. One practical choice is a simple dish or an early order, rather than a leisurely multi-course lunch. Food is not included, so carry a card or cash for the taverna.

The local wine served on board is included, but it is one glass of white wine in a small plastic cup. The wine itself may be good, but this is a modest refreshment, not a full tasting. Think of it as a pleasant drink during the return sail.

The return ride and what the small boat means

After Thirassia, the boat heads back to the Old Harbor. The ride gives you time to dry off, enjoy the breeze, and look back at the cliffs. The open water can be choppy, so a sweatshirt or light windbreaker is useful even on a hot day. Sprays can reach the boat, too.

The smaller vessel is a real advantage for reaching the stops before larger boats arrive. It also makes the group feel more manageable. The tradeoff is space. One review described the boat as small but comfortable, and that is the right expectation. You will not have unlimited room to stretch out or escape the wind.

The captain’s role is important here. The crew handles boarding, towels, noodles, and the boat schedule, but the experience is not a full educational tour. Some departures include little or no explanation of the volcano, hot springs, or Thirassia. If you want detailed geological or historical commentary, bring your own interest and read up before you go.

Communication before departure has been helpful, including directions sent through WhatsApp. Keep your phone available for any meeting updates, but remember that a mobile ticket does not remove the need to arrive at the correct port on time.

Is the $83 price good value?

At $83, this tour is reasonably priced for a five-hour boat outing that includes three major stops, a towel, water, a restroom, pool noodles, and one glass of wine. It is especially good value if you want to visit the volcano and hot springs but do not want to arrange separate boat transport.

The extra costs change the final price. Add €10 each way for the cable car and €5 for Nea Kameni entry. Food on Thirassia is also separate. Once you include those items, you should compare the full cost rather than looking only at the advertised tour price.

The strongest value comes from the combination of experiences. A boat ride alone can be cheaper, and a private charter can offer more comfort and flexibility. This trip gives you a practical middle ground: a limited group, a set route, and a chance to see volcanic sites plus Thirassia in one morning.

The main value risk is lost time. Everyone must board on schedule. If the group runs late, the hot-spring swim and Thirassia visit can become rushed. You are paying for access to several places, not a long stay at each one.

Who should book this Santorini boat tour?

I would choose this outing if you want active sightseeing and do not mind changing locations every hour or so. It suits couples, families with confident swimmers, and visitors who want more than Santorini’s cliffside views.

It is a good fit for you if you:

• Want to walk on a volcanic island
• Feel comfortable swimming in deep water
• Prefer a small boat to a large cruise vessel
• Like having free time instead of following a guide through every lane
• Want a quieter lunch stop on Thirassia
• Can handle sun, wind, rough ground, and a firm schedule

I would think twice if you need a fully guided experience, dislike open-water swimming, or want a slow, unhurried day. The volcano walk is self-guided, and the crew may focus on operating the boat rather than giving long explanations.

The tour is also weather dependent. If poor weather cancels it, you receive a different date or a full refund. For other cancellations, cancel at least 24 hours before the 10:15 a.m. start for a full refund. Changes or cancellations inside that window are not refunded.

My practical verdict

Book this tour if you want Santorini’s volcanic side in one compact outing. The volcano hike, sulfur springs, and quiet Thirassia stop create a better-rounded day than a simple caldera cruise, and the smaller group is a meaningful advantage.

Go prepared: wear sturdy shoes, bring cash, use dark swimwear, pack a light jacket, and be ready to swim. If you accept the tight timing and the lack of a formal guide, the $83 price gives you a solid way to see three very different sides of Santorini.

FAQ

How long does the Santorini boat tour last?

The tour lasts approximately five hours. The planned route includes about 20 minutes of sailing to Nea Kameni, 1 hour and 15 minutes at the volcano, 30 minutes at the hot springs, 1 hour and 15 minutes on Thirassia, and the return to Santorini Old Harbor.

Where does the tour begin and end?

It begins and ends at Santorini Old Harbor, also called Fira Port. The meeting point is Santorini Sea Trips, Anemos Old Port, Santorini, Thira 847 00, Greece.

What time does the tour start?

The scheduled start time is 10:15 a.m.

Is the volcano hike guided?

No. The hike on Nea Kameni is done on your own, without a guide. You are responsible for your safety and need to return to the boat on time.

How much does entry to the volcano cost?

Admission to Nea Kameni costs €5 per person and is not included in the tour price.

Do I need to pay for the cable car?

Yes. The cable car costs €10 each way and is not included. You can also reach the Old Harbor by walking down the steps or riding a traditional donkey.

Can non-swimmers use the hot springs?

The hot springs are reached by swimming from the boat, and the water is deep. Pool noodles are provided, but you should be comfortable swimming and able to keep swimming during the stop.

What is included in the tour?

The tour includes a restroom on board, foam pool noodles, free time on Thirassia, one glass of local white wine, a returnable towel, and one bottle of water. Food, the cable car, and the €5 Nea Kameni admission fee are not included.