Santorini's lagoon is a sea-flooded volcanic caldera - a near-complete ring of cliffs broken by a channel on the southwest, with two dark lava-dome islands rising from the water near its center. Toggle the caldera-depth marker to see how far the floor lies below the sea, and the clifftop marker to see how high the rim rises above it.
Published figures: caldera about 12 km by 7 km; maximum water depth inside the lagoon about 400 m (1,300 ft); the tallest clifftop rim (near Imerovigli) rises about 300 m (984 ft) above the sea - a total vertical relief of roughly 700 m (2,300 ft) from clifftop to caldera floor.
Drag to orbit and scroll or pinch to zoom. Everything renders on your device with WebGL.
Santorini Caldera 3D Explorer
This browser explorer shows the Santorini caldera as a sea-flooded volcanic ring: a near-complete rim of cliffs, tallest on the northwest side where the clifftop towns sit, broken by an open channel on the southwest where the sea flows in, with two dark lava-dome islands rising from the lagoon near the center. Two toggleable markers compare how far the caldera floor lies below the surface against how high the clifftop rim rises above it.
The caldera formed during the Minoan eruption, about 3,600 years ago (around 1600 BCE), one of the largest volcanic eruptions in recorded history. The eruption emptied the volcano's magma chamber and its summit collapsed, letting the sea flood in through the southwest breach to form today's lagoon. Nea Kameni and Palea Kameni, the dark islands near the lagoon's center, are younger lava domes built up by eruptions long after the original collapse - Nea Kameni last erupted in 1950 and its slopes still vent volcanic gas.
- Toggle the caldera-depth marker to see the roughly 400 m drop to the lagoon floor
- Toggle the clifftop-height marker to compare it against the roughly 300 m the rim rises above the sea
- Read caldera size, depth, clifftop height, and Kameni figures in the panel
- Drag to orbit, scroll or pinch to zoom
- Runs fully in the browser with the vendored three.js engine - no account, no upload
| Figure | Published value |
|---|---|
| Caldera dimensions | about 12 km by 7 km (7.5 by 4.3 miles) |
| Maximum caldera depth | about 400 m (1,300 ft) below sea level |
| Highest clifftop rim | about 300 m (984 ft) above sea level, near Imerovigli |
| Total vertical relief | about 700 m (2,300 ft), clifftop to caldera floor |
| Nea Kameni | the youngest lava-dome island, last erupted in 1950 and still vents gas |
| Caldera opening | breached on the southwest, letting ships sail directly into the lagoon |
| Formed | about 3,600 years ago (c. 1600 BCE) by the Minoan eruption |
For another volcanic caldera up close, open the Crater Lake 3D Explorer, or see a still-active volcanic island in the Krakatoa 3D Explorer.
The whole Santorini caldera - the breached rim, the clifftop cliffs, the Kameni islands, and the two depth markers - is built and drawn on your own device with WebGL through the site-vendored three.js engine. Orbit the scene to look down into the flooded ring, and toggle the markers to compare the sea-floor depth against the clifftop height. Nothing about your visit is uploaded to a server, and the engine loads once (about 0.7 MB) and is then cached.
This is an educational approximation - the caldera profile, island shapes, and vertical scale are schematic teaching cues, not survey data.
Frequently Asked Questions
How did the Santorini caldera form?
The Minoan eruption, about 3,600 years ago (c. 1600 BCE), emptied the volcano's magma chamber; the unsupported summit collapsed and the sea flooded in through a breach on the southwest, forming today's lagoon.
How deep is the caldera?
The floor of the flooded lagoon lies about 400 m (1,300 ft) below sea level at its deepest.
Why are the clifftop towns so high above the water?
The caldera rim on the northwest side, where towns like Fira and Imerovigli sit, rises about 300 m (984 ft) above the sea - the steep wall left by the collapse.
What are the Kameni islands?
Nea Kameni and Palea Kameni are younger lava-dome islands that grew inside the flooded caldera long after the original collapse. Nea Kameni last erupted in 1950 and still vents volcanic gas.
Can ships sail into the caldera?
Yes. The caldera rim is breached on the southwest side, leaving an open channel that lets ships sail directly into the lagoon.
Where is Santorini?
In the Aegean Sea, part of Greece's Cyclades island group.
Is this a scientific terrain model?
No. It is an educational explorer using published figures - the caldera profile, island shapes, and vertical scale are schematic teaching cues, not survey data.