Santorini, also known as Thira or Thera, is a Greek island located in the southern Aegean Sea, about 200 km (120 mi) southeast of the mainland. It is the largest island in a small, circular group of islands formed by the Santorini caldera. It is the southernmost island in the Cyclades group, covering an area of about 73 km (28 mi). According to the 2021 census, the population of Santorini was 15,480. The Santorini municipality includes the inhabited islands of Santorini and Therasia, as well as the uninhabited islands of Nea Kameni, Palaia Kameni, Aspronisi, Anydros, and Christiana. The total land area of the municipality is 90 km (35 mi). Santorini is part of the Thira regional unit.

Santorini is the most active volcanic area in the South Aegean Volcanic Arc. This volcanic arc is approximately 500 km (300 mi) long and 20 to 40 km (12 to 25 mi) wide. Volcanic activity in the region began around 3–4 million years ago, and volcanic activity on Thera started about 2 million years ago with lava flows from vents near Akrotiri. One of the largest volcanic eruptions in recorded history occurred on the island about 3,600 years ago, creating a large, water-filled caldera surrounded by thick layers of volcanic ash.

Names

The name "Santorini" comes from "Saint Irene," named after an old church in the village of Perissa. Influenced by the Venetian people, the island was called Santorini since at least the middle of the 12th century. The first recorded mention of this name was made by the geographer Muhammad al-Idrisi around 1154.

In ancient times, the island was known as "Thēra." Before that, ancient writers called it "Kallístē" (meaning "the most beautiful one") and, according to a modern tradition, "Strongýlē" (meaning "the circular one"). The name "Thēra" honored Theras, a leader of the Spartans who settled on the island and gave it its name. In the 19th century, the name "Thera" was officially revived for the island and its main city. However, the name "Santorini" remains commonly used today.

History

The island was the location of one of the largest volcanic eruptions in recorded history: the Minoan eruption, sometimes called the Thera eruption, which happened about 3,600 years ago during the height of the Minoan civilization. The eruption created a large hole, called a caldera, surrounded by layers of volcanic ash that were hundreds of meters deep. Some people think the huge Santorini volcanic eruption may have inspired the legend of the lost city of Atlantis. The eruption lasted for weeks and caused huge tsunami waves.

The region became active with volcanic activity around 3–4 million years ago. Volcanic activity on Thera began about 2 million years ago, when lava from vents near Akrotiri was released.

Starting in 1967, excavations at the Akrotiri site, led by Spyridon Marinatos, made Thera (not known by this name at the time) the best-known Minoan site outside Crete, the home of the Minoan culture. Only the southern tip of a large town has been uncovered, but it shows multi-level buildings, streets, and squares with walls as tall as eight meters, all covered in hardened ash from the Thera eruption. This site was not a palace like those in Crete or a place for storing goods. The excellent construction and colorful wall paintings suggest a complex community. A loom found at the site shows that textiles were made for trade. This Bronze Age civilization existed between 3000 and 2000 BC, reaching its peak between 2000 and 1630 BC.

Many of the houses in Akrotiri are large, some with three floors. The streets, squares, and walls, sometimes as tall as eight meters, show that this was a major town. Much of the town is preserved in layers of volcanic material. The houses contain large ceramic jars, mills, pottery, and many stone staircases that are still intact. Noted remains include wall paintings that have kept their original colors because they were covered by many meters of volcanic ash. The artwork shows that the people were skilled and had wealth. Some paintings show antelopes, a man holding fish, a group of pleasure boats with dolphins, and women sitting under canopies. Other paintings show people gathering saffron and offering it to a seated woman, possibly a goddess. These paintings do not match the themes of Greek art from 510 to 323 BC, which often showed Greek gods.

The town had an advanced drainage system. Pipes with running water and water closets found at Akrotiri are the oldest of their kind. The pipes were part of two systems, showing that the people used both hot and cold water. The hot water likely came from geothermal heat, because of the volcano’s closeness.

The well-preserved ruins of the ancient town are often compared to the ruins of Pompeii in Italy. In September 2005, the canopy covering the ruins collapsed, killing one tourist and injuring seven. The site was closed until April 2012 while a new canopy was built.

The oldest signs of human settlement in the area date back to the Late Neolithic period (4th millennium BC or earlier). Around 2000–1650 BC, Akrotiri became a major port in the Aegean, with items found from Crete, Anatolia, Cyprus, Syria, Egypt, the Dodecanese, and the Greek mainland.

The Minoan eruption is an important event for dating the second millennium BC in the Aegean, because evidence of the eruption is found throughout the region. The eruption happened during the "Late Minoan IA" period on Crete and the "Late Cycladic I" period on nearby islands.

Archaeological evidence, based on the timeline of Bronze Age Mediterranean cultures, dates the eruption to about 1500 BC. However, carbon dating suggests the eruption happened between 1645–1600 BC, and tree ring data gives a date of 1628 BC. These differences have caused questions about earlier dating methods.

In The Parting of the Sea: How Volcanoes, Earthquakes, and Plagues Shaped the Exodus Story, geologist Barbara J. Sivertsen suggests a connection between the eruption and the plagues described in the Exodus story.

Santorini was not occupied during the rest of the Bronze Age, while the Greeks took control of Crete. At Knossos, in a context from the 14th century BC, seven Linear B texts mention "all the deities" but

Geography

The Cyclades are part of a group of rocks that have changed over time, known as the Cycladic Massif. This group of rocks formed during the Miocene period and was folded and changed by the Alpine orogeny, a mountain-building event, about 60 million years ago. Thera is built on a small base of non-volcanic rock that was once a non-volcanic island, measuring about 9 kilometers by 6 kilometers. This base is mostly made of metamorphosed limestone and schist, which formed during the Alpine Orogeny. These non-volcanic rocks can be seen in places like Mikros Profititis Ilias, Mesa Vouno, the Gavrillos ridge, Pyrgos, Monolithos, and the inner side of the caldera wall between Cape Plaka and Athinios.

The metamorphic grade of these rocks is called blueschist facies, which forms when tectonic forces push the African Plate under the Eurasian Plate. This subduction happened between the Oligocene and Miocene periods, and the blueschist facies marks the southernmost part of the Cycladic blueschist belt.

Volcanic activity on Santorini is caused by the Hellenic subduction zone, which is located southwest of Crete. Here, the oceanic crust of the African Plate is being pushed under Greece and the Aegean Sea, which has thin continental crust. This movement creates the Hellenic arc, a chain of volcanic centers that includes Santorini and others like Methana, Milos, and Kos.

Santorini was formed by repeated cycles of shield volcano building followed by caldera collapses. The inner coast near the caldera has steep cliffs over 300 meters high, showing layers of solidified lava stacked on top of each other, with towns built on the cliff edges. The land slopes outward from the caldera, and the outer beaches are flat and shallow. Beach sand colors vary depending on the exposed geological layers, such as the Red Beach, Black Beach, and White Beach. The water near darker beaches is warmer because the lava absorbs heat.

Santorini and its surrounding islands, including Thera, Thirasia, Aspronisi, Palea, and Nea Kameni, were created by volcanic activity.

Santorini has erupted many times, with some eruptions being very explosive. At least twelve large explosive eruptions have occurred, with at least four forming calderas. The most famous eruption is the Minoan eruption, described below. Volcanic materials range from basalt to rhyolite, with rhyolite linked to the most explosive eruptions.

The earliest eruptions, which happened underwater, occurred on the Akrotiri Peninsula between 650,000 and 550,000 years ago. These eruptions are chemically different from later ones because they contain amphiboles.

Over the past 360,000 years, two major volcanic cycles have occurred, each ending with two caldera-forming eruptions. These cycles stop when magma changes to a rhyolitic composition, leading to explosive eruptions. Between caldera-forming eruptions, smaller eruptions and lava flows build up volcanic cones, which may slow magma movement. This allows magma to form large chambers where it can evolve into more silicic compositions. When this happens, a large eruption destroys the cone. The Kameni islands in the lagoon are a recent example of such a cone, with much of it underwater.

During the Bronze Age, Santorini experienced the Minoan eruption, one of the largest volcanic eruptions in human history. The eruption occurred near the current island of Nea Kameni in the caldera. The caldera was formed hundreds of thousands of years ago when the center of a circular island collapsed due to magma chamber emptying during an eruption. Since then, the caldera has been filled multiple times by ignimbrite, most recently 21,000 years ago. The northern part of the caldera was refilled by the volcano and collapsed again during the Minoan eruption. Before the eruption, the caldera formed a nearly complete ring with only one entrance between Aspronisi and Thera. The eruption destroyed parts of the ring, creating two new channels.

On Santorini, a layer of white volcanic ash from the Minoan eruption is up to 60 meters thick, covering the ground level before the eruption. This layer has three distinct bands, showing different eruption phases. In 2006, scientists discovered that the Minoan eruption was much larger than previously thought, expelling 61 cubic kilometers of magma and rock into the atmosphere, compared to earlier estimates of 39 cubic kilometers. This eruption released more material than only a few other eruptions in the past 5,000 years, including Mount Tambora in 1815, the Taupo Volcano in 181 AD, and possibly Baekdu Mountain in 946 AD.

The Minoan eruption has been linked to ancient stories like Atlantis and the Exodus, though these stories are not supported by archaeological evidence. They remain popular in pseudohistory and pseudoarchaeology.

After the Minoan eruption, volcanic activity has focused on the Kameni islands in the lagoon. These islands formed after the Minoan eruption, with the first emerging from the sea in 197 BC. Nine eruptions have been recorded since then, with the last ending in 1950.

In 1707, an underwater volcano broke the sea surface, forming the current center of activity at Nea Kameni. Eruptions centered there continued, with three recorded in the 20th century, the last in 1950. Santorini was also hit by a major earthquake in 1956. While the volcano is currently dormant, steam and carbon dioxide are released from the active crater on Nea Kameni.

In 2011 and 2012, small tremors and strange gas smells led scientists to use satellite radar technology. This revealed that the magma chamber under the volcano expanded by 10 to 20 million cubic meters between January 2011 and April 2012. This expansion caused parts of the island to rise by 8 to 14 centimeters. Scientists said this magma injection was equivalent to 20 years of normal volcanic activity.

At the start of February 2025, hundreds of minor earthquakes up to magnitude 5 occurred near Santorini, mostly around the small islet of Anydros, northeast of the island. About 9,000 people left the island, which has a population of 15,500, due to potential seismic activity lasting weeks. The tremors were caused by tectonic plate movements, not volcanic activity.

Climate

According to the National Observatory of Athens, Santorini has a hot semi-arid climate (Köppen climate classification: BSh) with features similar to the Mediterranean climate (Csa), such as dry summers and wetter winters. The island receives an average of about 270 mm (11 inches) of rain each year and has an average yearly temperature of approximately 19°C (66°F).

Economy

Santorini's main industry is tourism, especially during the summer months. Agriculture, including a wine industry, also plays a role in the island's economy. Before 1960, the island's economy relied mainly on farming and trade.

In the middle of the 19th century, Santorini had strong trade connections with foreign countries, particularly Russia, where it exported all of its wine. The island's unique volcanic soil and climate help produce special crops, such as the Santorini cherry tomato. Growing grapes for wine, known as viticulture, has a long history on the island, but it has decreased over time due to the rise in tourism. Viticulture remains the most important part of Santorini's agriculture.

Today, Santorini has a small wine industry that uses the Assyrtiko grape, along with other local white and red grape varieties. The vines are very old and resistant to a disease called phylloxera, which is believed to be due to the well-drained volcanic soil. These vines are planted far apart because they rely on dew for water. They are often trained in low, spiraling baskets to protect the grapes from strong winds.

A famous wine from Santorini is Vinsanto, a sweet and strong dessert wine made from dried Assyrtiko, Athiri, and Aidani grapes. It is aged in barrels for many years, sometimes up to 20 to 25 years. Vinsanto has a dark, amber-orange color and a rich flavor with notes of citrus, minerals, nuts, raisins, figs, honey, and tea. It is well-known worldwide.

White wines from Santorini are very dry and have strong citrus and mineral smells, influenced by the island's volcanic soil. Some white wines also have a slight frankincense-like aroma from aging. Growing grapes on Santorini is difficult because the hot, dry climate makes the soil less productive. The amount of wine produced per hectare is only 10 to 20% of what is common in places like France or California. Santorini's wines are protected by special labels called "Vinsanto" and "Santorini" designations of origin.

A brewery named the Santorini Brewing Company began operating on the island in 2011, located in the area where wine is produced.

Governance

The current municipality of Thera (officially known as "Thira," Greek: Δήμος Θήρας) includes all settlements on the islands of Santorini and Therasia. It was created in 2011 during a local government reorganization by combining the former municipalities of Oia and Thera.

Oia is now referred to as a Κοινότητα (community) within the municipality of Thera. It includes the local subdivisions (Greek: τοπικό διαμέρισμα) of Therasia and Oia.

The municipality of Thera includes 12 additional local subdivisions on Santorini: Akrotiri, Emporio, Episkopis Gonia, Exo Gonia, Imerovigli, Karterados, Megalohori, Mesaria, Pyrgos Kallistis, Thera (the official seat of the municipality), Vothon, and Vourvoulos.

Attractions

The traditional buildings in Santorini are similar to those in other Cyclades islands. These homes are usually low and cube-shaped, made from local stone. Their walls are often painted white or with colors made from volcanic ash. In recent years, these colors have become more common than white on house walls, following the style of Santorini’s architecture before the big earthquake in 1956. A special feature of Santorini’s homes is the use of hypóskapha, which are rooms built by digging sideways or downward into the soft pumice rock around houses. These rooms stay cool in the summer and warm in the winter because the air-filled pumice acts as insulation. They are also used to store goods, especially for keeping wine, as seen in the Kánava wineries of Santorini.

In 1956, strong earthquakes destroyed many buildings on the island. Half of the homes were completely ruined, and many others needed repairs. The underground rooms near the ridge above the caldera were especially damaged because the ground there was unstable. People living in these areas had to leave their homes. Many residents of Santorini moved to Piraeus and Athens during this time.

Between the 15th and 16th centuries, pirates threatened the Cyclades islands. These pirates took food and goods, forced people into slavery, and sold them in markets. The small bays of Santorini were good places for pirates to hide. To protect themselves, the islanders built their homes on high, hard-to-reach ground, and placed them close together. Their homes had thick outer walls with no windows, forming a protective barrier around villages. In addition, other types of defenses were built across the island to keep the people safe.

Infrastructure

Electricity for Santorini and Therasia is mainly powered by the Thira Autonomous Power Station, located in Monolithos on the eastern side of Santorini. The power station is owned by the Public Power Corporation (PPC) and uses generators powered by diesel engines and gas turbines. Together, the two islands have a total power generation capacity of 75.09 MW from thermal sources and 0.25 MW from renewable sources. A project costing €124 million is currently underway as part of the Cyclades Interconnection Project to connect the island to Naxos via an underwater cable, linking it to the mainland by 2023.

A fire at the Monolithos power station on August 13, 2018, caused a complete electricity outage across both islands. Electricity was restored to all but 10% of consumers within four days. Ships were sent to deliver two power generators to help restore the electricity supply.

Electricity is distributed across the islands by the Hellenic Electricity Distribution System Operator (HEDNO S.A. or DEDDIE S.A.), a company fully owned by PPC. A cable connects the electrical systems of Santorini and Therasia.

The central bus station is in Fira, the island’s capital, where buses run frequently to most areas and tourist sites.

Santorini is connected by ferry to Piraeus daily throughout the year, with up to five direct crossings during the summer.

Santorini has a major airport located about 6 kilometers southeast of Thera. The main runway is 2,125 meters long and can handle aircraft such as Boeing 757, Boeing 737, Airbus A320, and others. Airlines like Olympic Air, Aegean Airlines, Ryanair, and Sky Express operate flights to the island, with additional charter flights during the summer. Buses, taxis, hotel pickups, and rental cars provide transportation to and from the airport.

Buses connect Fira to most parts of the island.

Santorini has two ports: Athinios (Ferry Port) and Skala (Old Port). Cruise ships stop near Skala, where passengers are transported to shore by local boatmen. From Skala, visitors can reach Fira by cable car, on foot, or by donkeys and mules. The use of donkeys for tourism has faced criticism from animal rights groups due to concerns about their treatment and lack of water or rest. Tour boats also depart from Skala to destinations like Nea Kameni.

Santorini lies in a rain shadow between the mountains of Crete and the Peloponnese, leading to limited rainfall since the island’s volcanic eruption. Combined with its small size, lack of rivers, and volcanic soil, this made surface water scarce. The island has only one spring, Zoodochos Pigi, which encouraged the use of underground cisterns to collect rainwater from rooftops and courtyards. In the 20th century, water was also imported from other parts of Greece. Due to the dry climate, islanders grew crops like grapes and olives that required little water, relying on morning dew.

Many cisterns stopped being used after the 1956 earthquake. As tourism grew, existing water collection methods could not meet demand, leading to the construction of desalination plants. These plants now provide non-potable water to most residents, causing many historic cisterns to fall into disrepair.

The first desalination plant was built in Oia in 1992, funded by businessman Aristeidis Alafouzos. By 2003, the plant had three units, two of which were donated by Alafouzos. As of 2020, the plant has six units with a daily capacity of 2,800 cubic meters.

Other desalination plants are located in Aghia Paraskevi (5,000 cubic meters per day), Fira (1,200 cubic meters per day), Akrotiri (650 cubic meters per day), Exo Gialos (2,000 cubic meters per day), and Therasia (350 cubic meters per day). Small independent water production units also operate in Kamari, Emporio, Messaria, and Thirasia.

Water supply and sewage systems on Santorini and Therasia are managed by DEYA Thiras, a municipal company formed in 2011 by merging two earlier water and sewage companies. DEYA Thiras oversees the planning, construction, and maintenance of desalination plants, pumping wells, irrigation, drainage, and wastewater treatment. The Loulas and Evangelos Nomikos Foundation has supported projects to improve these systems.

In popular culture

The movie Summer Lovers (1982) was filmed on location here.

The island was used as a filming location in the 2005 film The Sisterhood of the Traveling Pants and its sequel.

Santorini inspired French pop singer Nolwenn Leroy to create her song "Mystère," which was released on her 2005 album Histoires Naturelles ("Aux criques de Santorin").

Australian singer Donny Benét recorded a song called "Santorini," which was released on his 2018 album The Don.

The Santorini Film Festival is held every year at the open-air cinema, Cinema Kamari, in Santorini.

American hip hop artist Rick Ross has a song titled "Santorini Greece," and the music video for this song was filmed on the island in 2017.

Santorini appears in the 2014 video game Call of Duty: Advanced Warfare during the mission "Manhunt." Players track a target and chase them through the streets.

The 2018 video game Assassin's Creed Odyssey includes a DLC called "Fate of Atlantis," where a gateway to the mythical city of Atlantis is found in a temple under the island of Thera.

The board game Santorini, inspired by the architecture of the island's cliffside villages, was published in 2004 by Gordon Hamilton.

The K-Pop group ARTMS had a photoshoot in Santorini for their 2024 Season's Greetings.

In the film The Parting of the Sea: How Volcanoes, Earthquakes, and Plagues Shaped the Exodus Story, geologist Barbara J. Sivertsen tries to connect the eruption of Santorini around 1600 BC to the Exodus of the Israelites from Egypt as described in the Bible.