Ancient Acrotiri is a pre-historic Cycladic village and was likely a Minoan colony. In approximately 1500 BC it was covered with ash from the eruption of the island's volcano. Ancient Acrotiri was first unearthed in 1967 by Professor Spiros Marinatos who, in 1974 fell to his death during the dig, and is buried, by his express wish, on site. The site suffered further mishap in 2005 when the roof partially collapsed killing a visitor and injuring several others.
Situated 15 km from Fira and1 km from modern Acrotiri (pop 210), the site is roofed to protect it from the elements (above). It rests in a ravine below the modern day village of Acrotiri with its ruined medieval castle and near by, red beach.
The ancient occupants of Acrotiri appear to have had ample time to escape the massive destruction to the island since no jewelry or human remains have been discovered. What they left behind however is quite interesting and brings to mind the finds of Herculaneum similarly buried under volcanic tephra. The most interesting finds are the beautifully executed wall paintings or frescos of which the best are in the National Archeology Museum Athens.
Of the two "major" ancient sites on Santorini, Acrotiri and ancient Thira, if you have only time to visit one, visit Acrotiri.
The city of Ancient Thira was built on the mountain slope 12 km SE of Fira and composed of tiers upheld by extensive foundations. A settlement existed here in archaic times c 9th C BC. The majority of the present ruins were constructed under the Ptolemies (300-145 BC) who used the island as a naval base from which to control the Aegean and the latter ruins date from the Byzantine period.
The cities site is140 meters wide and 800 meters long and built upon a ridge called middle mountain. During the Byzantine era it was surrounded by a wall with a main street traversing the entire length with numerous side streets. The central street leads to the Agora (left) which had a row of shops on its north side. Its southern boundary was the Doric Royal Stoa with two aisles and a colonnade along one wall. At the southern end of the city is the gymnasium where in the 7th c BC young, nude boys practiced athletic events and whom were much admired by their fellows as attested to by numerous erotic graffiti carved into the walls. Many of the houses have fine decorative mosaics and advanced plumbing systems. The impressive Terrace of the Festivals and the 6th c BC Temple of Apollo Karneios were the scene of Doric cult worship. Read more about Ancient Thira