Akrotiri is a village in Santorini.
It is on the southwestern side of Santorini and though it offers great view of the caldera and volcano, like Fira and Ia is not that touristically developped. It has become famous, due to the ancient settlement of Aktrotiri, which is located next the modern Akrotiri village
Start with Santorini#Get_in.
From anywhere on Santorini: by taxi or local bus.
Archeological Site of Akrotiri
It was back in the end 19th century, that the volcanic Theran earth was excavated to provide first material for the construction of the Suez Canal. There have been traces of a prehistoric settlement, but it wasn’t until 1967 when the excavations at the so called ancient Akrotiri started. The most important excavations, which brought to light multi-level buildings and masterpiece-wall paintings, were conducted by the archaeologist Spryridon Marinatos, a professor at the University of Athens.
The site was settled in the mid 5th millennium BC (Neolithic age).
Akrotiti settlement is 1.2 hectares and one of the best preserved all over Greece and we owe that to the same factor, that caused its destruction. After the eruption of the volcano in the 17 century B.C. , the whole island, and Akrotiri as well, has been covered with volcanic material. These material has, however, played major role in the protection of the ancient settlement and especially its wall paintings.
Here you can clearly see the layered effect of different debris from such an event. In the layer of light dust there is pollen and evidence of olive tree leaves showing that this occurred in Spring time. There is a lack of ornamental or valuable items as investigators believe that there was a minor earthquake/eruption 1-2 weeks prior to the main eruption which allowed the residents to pack up their valuables and get ready to leave. This can be seen also by the stone star case which is beautifully cracked in the along its mid-line. There are vessels evident that were used for transportation and storage of daily goods such as olive oil, figs, snails, grains, water etc.
You can see the triangular square where there is a 3 story house that was painted with maritime paintings on the walls (the most famous of which shows a young boy showing off his catch of fish, demonstrating his skills). Opposite this house you can see a toilet and the plumbing employed (running through the walls of the house). There is also a main thorough fair that had sewage channels, smaller streets and buried offerings. There was also a painting of ancient boats that demonstrated the use of large vessels that would have been able to trade between local areas around the Aegean and to Egypt. Before this painting there was no evidence of the types of sea going vessels from this era. This trading port played a major role in the transportation of copper from Cyprus to Crete which enabled the city to proper and develop an advanced cosmopolitan character.
The only valuable article found so far was a golden horse that was hollow! This was done by quite an advanced technique using a wax mold. This was found in a box buried on a small street.
It is believed the current excavation site is only 10% of the entire site. Guided tours are also available in the Archaeological site. 
From Akrotiri, you can walk to the Red Beach or get a boat to it, which also makes stops at the White Beach and the Black Beach. It is 5 euros return but you don't receive any ticket or receipt (nor do they have the means to give you one). However, there is only one boat so they trust if you come back by it, you must have come so you aren't asked to pay again, only when you leave Akrotiri. The only stop with a pier is Akrotiri so if you intend to get off, tell them explicitly or they won't know to stop (though they often ask) and be prepared to get off directly into the sea and walk through the water to get to the beach. They always stop in waters shallow enough to walk in for adults (highest it comes to is the waist) so it is possible to bring bags, but make sure you can lift them above your head.