Santorini has a great history, starting from the Bronze Age.  The large excavation at Akrotiri, has verified that there was a great civilization on the island.  The excavations which started in 1956 brought to light an ancient city very well preserved, which was entirely buried beneath a very thick layer of ash from the great eruption in 1625 as the latest studies have shown.

Herodotus,  who speaks about the early history of Santorini, tells us that the island was initially called Strongyle, the Round One, from its shape, later Kallisti, the Fairest One, because of its beauty, and after the Lacedaemonians' arrival and the foundation of their colony, they gave the island the name of their king, Thera.  The name Santorini was given by the Crusaders after a small chapel of Agia Irene (Santa Irene).

The Lost Atlantis

There is a story thousands of years old about a "lost island" in the Atlantic Ocean. The story was told by the ancient Greeks, and had been handed down from father to son for many generations before the Greek philosopher Plato wrote a famous story about it, about 375 BC.
The island of Atlantis, according to Plato's story, was really a series of islands. Imagine in the center a hill, surrounded by a ring of water; the ring of water surrounded by a circle of land, then another ring of water and one of land, until there were nine rings of water and nine of land. The islands had been created by Neptune, god of the sea, for Cleito, his beloved. From their children the king and people of Atlantis were descended. The island was very rich, and the people content. The city was built of black and red stone; the roofs of the houses were of red copper and flashed in the sun; and there were two beautiful temples, one surrounded by a golden wall and the other with silver walls, golden pinnacles, and a roof of ivory.

In 1967, a city buried by a volcanic eruption in 1500 BC., was found on Santorini. Archaeologists say this might be Atlantis.