The Santorini hot springs are warm, iron-rich volcanic waters in a sheltered cove of Palea Kameni island, reached only by boat and included as a swim stop on most caldera cruises. The rust-coloured water sits at around 30 to 35 degrees. This guide covers the springs, the water, how to visit and tips for swimming.
The hot springs are a highlight of the caldera in the wider Santorini travel guide. They lie at the heart of the bay. The sections below cover the springs.
What are the Santorini hot springs?
The Santorini hot springs are warm, mineral-rich volcanic waters in a small cove on Palea Kameni, one of the two volcanic islets in the caldera. Heated by lingering geothermal activity, the iron and sulphur tint the water a cloudy rust-orange, and a swim there is a popular stop on caldera boat cruises.
The hot springs are one of the caldera’s most enjoyable experiences. They rise in a sheltered bay on Palea Kameni, the older of the two dark volcanic islands that have grown at the centre of the flooded crater, where geothermal heat still warms the seawater. Rich in iron and sulphur, the spring water is cloudy and rust-orange, with a faint eggy smell, and gathers in a shallow cove the boats anchor just outside. Swimming in the warm, coloured water with the bare volcanic island rising beside you is a memorable, slightly surreal treat, and it is built into the great majority of Santorini’s caldera cruises, set within the wider Santorini volcano. The water is gently warm.
How warm is the water?
The hot springs water sits at around 30 to 35 degrees Celsius, pleasantly warm rather than hot, and noticeably warmer than the cool open Aegean around it. The temperature varies across the cove, hottest near the shore where the springs rise, so you swim from the cooler sea into a distinctly warmer patch.
The warmth is gentle, not scalding. The spring water holds at roughly 30 to 35 degrees, warm and soothing but a long way from a hot tub, and the effect is most striking because of the contrast: the surrounding caldera sea is cool, so as you swim in towards the cove you suddenly feel the water turn pleasantly warm within a few strokes. The heat is strongest close to the shore, where the geothermal water seeps up, and fades as you move back out. The mineral-laden water is said to be good for the skin, and floating in it amid the volcanic scenery is the real reward rather than the modest temperature, set out alongside the guide to Santorini day trips. Reaching it needs a boat.
How do you visit the hot springs?
You visit the hot springs by boat, as there is no land access to Palea Kameni’s cove. Most caldera cruises from the Old Port below Fira combine the springs with a hike up the Nea Kameni volcano, and the boat anchors about 50 metres out so you swim in to the warm water.
A boat trip is the only way to reach the springs. Palea Kameni’s warm cove has no road or path access, so visitors come on the caldera cruises that sail out from the Old Port below Fira and from Ammoudi Bay below Oia. Almost all of these combine the hot springs with a hike to the craters of the neighbouring volcanic islet, Nea Kameni, making a classic half-day on the water. Because the cove is shallow and the seabed delicate, the boats anchor around 50 metres offshore, so you jump or climb down from the boat and swim the short distance in to the warm zone yourself, then swim back when the captain calls time, typically after 20 to 30 minutes, set out alongside the guides to Santorini boat tours and the Old Port. A few tips help.
What should you know before swimming?
Before swimming, wear a dark or old swimsuit, as the iron-rich water stains light fabric a yellow-brown that does not wash out, and bring water shoes for the rocky entry. You must be a confident swimmer for the 50-metre swim, and the open water is cool, so the warm cove is the reward.
A little preparation makes the swim trouble-free. The single most important tip is to wear a dark-coloured or older swimsuit and leave white or pale ones on the boat, because the iron in the water permanently stains light fabric a rusty yellow-brown. Water shoes help with the rocky, gritty entry, and because the boat anchors offshore in cool, sometimes choppy water, you should be a reasonably confident swimmer, as there is a real swim out and back to the cove. The cooler open sea on the way in surprises some people, so it is the warm, sheltered cove that is the prize. With the right swimsuit and a little nerve, it is a genuine highlight, set out alongside the guide to Santorini beaches. The questions below cover the points travellers ask most.
Frequently Asked Questions
What are the Santorini hot springs?
The Santorini hot springs are warm, iron-rich volcanic waters in a cove of Palea Kameni island in the caldera, reached by boat. The minerals turn the water a rust-orange, and a swim there at around 30 to 35 degrees is a popular stop on most caldera cruises from the Old Port.
How do you get to the Santorini hot springs?
You get to the hot springs only by boat, on the caldera cruises that sail from the Old Port below Fira and from Ammoudi Bay, usually combined with a hike up the Nea Kameni volcano. The boat anchors about 50 metres out, so you swim in to the warm cove yourself.
Should you wear an old swimsuit in the hot springs?
You should wear a dark or old swimsuit in the hot springs, as the iron-rich water permanently stains light fabric a rusty yellow-brown. Bring water shoes for the rocky entry, and be a confident swimmer, since the boat moors roughly 50 metres out from the warm cove.