From the deck

Santorini's volcano history, read from the water

8 min read

Santorini volcano history since 1707 is short and legible. Nine subaerial eruptions built the Kameni islands: 197 BC, AD 46–47, AD 726, 1570/1573, 1707–1711, 1866–1870, 1925–1928, 1939–1941 and 1950. The 1707–1711 episode raised Nea Kameni itself. The 1950 eruption is the most recent to date.

The dark island in the middle of the caldera is younger than a good many of the buildings you walked past in Fira this morning. That is the fact worth carrying onto a boat.

Everything below comes from the peer-reviewed eruption sequence in Nomikou and colleagues, published in *GeoResJ*, and from the Nea Kameni and Palea Kameni records, all checked on 25 August 2026.

The numbers

Nine eruptions, and what each one left behind

These are the nine subaerial eruptions that define the present shape of the Kameni islands. Everything in the third column is visible from a boat, which is not true of most volcano timelines.

Date	What happened	What is left to look at
197 BC	The first of the nine. Land begins to reappear inside a caldera that had been empty water since the Minoan eruption.	The low, dark, southern islet: Palea Kameni, the old burnt island.
AD 46–47	Palea Kameni grows. In antiquity the island was called Hiera.	The 0.5 km² of pumice and black dacite lava you swim beside at the hot springs.
AD 726	A submarine explosive eruption at Palea Kameni.	The bay of Agios Nikolaos, its chapel, and the vents that still leak iron into the water.
1570 / 1573	Activity resumes after eight centuries of quiet. Sources give the date both ways.	The oldest lava on Nea Kameni's southern side, weathered brown-grey rather than black.
1707–1711	The episode that built Nea Kameni proper — the new burnt island — out of open water.	The core of the island in front of you. It is younger than the oldest houses on the rim above it.
1866–1870	Four years of activity producing the Georgios dome.	A distinct lobe on the island's western flank, joined on to what came before it.
1925–1928	Three years of activity producing the Daphne crater.	The crater complex the marked path climbs to, roughly 130 m above the landing.
1939–1941	The eighth of the nine, through the years the lighthouse round the corner was dark.	More lava on the same island, still unvegetated after eighty-five years.
1950	A small lava-dome extrusion. The most recent eruption to date.	The youngest land in the eastern Mediterranean, and the freshest black rock on the whole horizon.

Sequence per Nomikou et al., GeoResJ, with the Georgios and Daphne attributions and the 1950 date as published on the Nea Kameni record (both seen 25 August 2026). Nea Kameni today is 3.4 km², about 2 km across, and 114 m at its highest point.

What "still active" actually means here

It does not mean smoke. It means somebody is watching, and has instruments doing it.

The volcano is quiescent. The last eruption was in 1950 and nothing has erupted since. It is monitored continuously by ISMOSAV, the Institute for the Study and Monitoring of the Santorini Volcano, and Nea Kameni is a protected scientific site as well as a national geological park.

That is the whole of the honest answer. A volcano with a monitoring institute pointed at it is a volcano being taken seriously, not one about to do something on your Tuesday.

There is one thing we will not put a number on. A period of unrest in the caldera in 2011 and 2012 is widely discussed, and our own sourced research file does not carry it. Rather than repeat figures we have not checked, we will point you at ISMOSAV's own published record and leave it there.

What our sources do carry is more recent and more mundane. An earthquake swarm around Santorini, reported by different outlets as late 2025 or early February 2025, brought down rock at Red Beach and is one of the reasons cruise numbers fell that year. Nobody on a boat was worried. It changed a beach and a booking curve, not a horizon.

From the crater rim, and from a boat lying off

The two are not competing versions of the same thing. They show you different objects, and only one of them costs you an afternoon.

What you want to see	From the crater rim on Nea Kameni	From a boat lying off
The fumaroles	Yes. Steam venting through yellow sulphur deposits, close enough to smell. This is the reason to land.	No. They sit up at the rim and you cannot see into the crater from sea level.
The lava lobes in section	Poorly. You are standing on top of them, so they read as loose black scree in every direction.	Clearly. From the water the flows show as stacked lobes with a waterline cut through them, oldest to youngest, left to right.
The colour of the rock	Uniform black-grey underfoot, flattened by overhead sun and dust.	Brown, rust, grey and true black, separated by age, with reflected light coming up off the sea onto the face.
Palea Kameni beside it	A shape across the water, seen from above.	You swim in it. The iron staining the water is the same system, still running.
The caldera wall behind you	Excellent, and the main prize of the climb: 300 m of layered cliff with the villages on the lip.	Also excellent, and closer, and you are inside the basin rather than looking across it.
What it costs you	The park fee, published at €5 per person and collected in cash by rangers — there are no card facilities on the island. Then 45 to 75 minutes on loose scree with no shade, no water and no shelter.	Nothing extra, and no walking. Our boats do not land, so the volcano is a thing you look at and sail past rather than climb.

Park fee, path lengths and the absence of shade and water are as published on the Nea Kameni records seen 25 August 2026. The fee is not inside any of our fares, and walking on the volcano is not part of any of our cruises.

Reading the islands as you pass

There is a trick to looking at the Kameni islands, and it is to compare them with Aspronisi rather than with each other.

Aspronisi is the small white island in the south-western gap of the rim. Its base is dark lava. Above that sit thick pale layers of pumice and ash. The black is what the island was before the Minoan eruption. The white is the eruption itself, lying on top of it.

Now look back at Nea Kameni. There is no white cap anywhere on it, because it did not exist when the ash fell. Everything you can see there arrived afterwards, from below, in the nine episodes in the table above.

One island records the hole being blown. The other records the hole being slowly filled back in. They are 3 km apart and you pass both inside twenty minutes.

That is the sentence we usually say at the rail, somewhere off the lighthouse, when the caldera opens up ahead of the boat.

We do not land on the volcano

Our catamaran cruises anchor offshore and never put guests ashore on Nea Kameni. The crater walk needs the national park fee and 45 to 75 minutes on open scree, and it would take the afternoon that the swimming and the meal are in.

If the crater rim is the thing you came for, book a dedicated volcano boat and do it properly. It is a different day, not a worse one.

Ready when you are

See it from the water

Send us your date and how many of you there are. The volcano sits in the middle of every caldera cruise we run, and the hot springs on Palea Kameni are a swim rather than a viewpoint.

Check availability & book

Call the harbour office+30 698 977 1888

Common questions

When did the Santorini volcano last erupt?

In 1950, a small lava-dome extrusion on Nea Kameni. It is the most recent eruption to date and the ninth in the sequence that began in 197 BC. Nothing has erupted since, and the island is monitored continuously by ISMOSAV as a protected scientific site.

Is the Santorini volcano still active?

Yes, in the technical sense: it is a live volcanic system that is quiescent and continuously monitored, not extinct. It has not erupted since 1950. Active describes the system and the monitoring rather than anything you will see happening from the deck of a boat.

What are Nea Kameni and Palea Kameni?

The two dark islets in the middle of the caldera, meaning new burnt and old burnt island. They were built up over roughly two thousand years by repeated dacite eruptions after the caldera collapsed. Nea Kameni carries the walkable crater; Palea Kameni carries the warm springs.

How much is the Nea Kameni entrance fee?

Nea Kameni is a national geological park with a separate landing fee, widely published at €5 per person and collected in cash by rangers at the trailhead. There are no card facilities on the island. It is not inside our fares, because our cruises do not land there at all.

How long is the volcano hike?

The marked gravel path climbs roughly 130 m to the crater rim. Published figures give 20 to 30 minutes for the ascent and 45 to 75 minutes for the full circuit. There is no shade, no water and no shelter anywhere on the island, and the surface is loose volcanic scree.

Why do our cruises pass the volcano instead of landing on it?

Because a five-hour cruise cannot hold both. Landing means the park fee, a tender ashore and up to 75 minutes on open scree in the middle of the day. We spend that time on the water instead, at the hot springs on Palea Kameni, with the meal cooked while you swim.

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

Updated August 2026