Ancient Thera stands on Mesa Vouno, at an altitude of 396 m. It is an ancient city named after mythical ruler of the island. It was founded in the 9th century BC by Dorian settlers, led by Theras; habitation continued until the early Byzantine era. The position is naturally fortified because the steep slopes of the mountain made the city inaccessible from land or sea and also a great observatory to the SE Aegean Sea. Public and private buildings are built along the main axis of the city in direction from the NE to the SE corner of the rock. Smaller cobbled streets adapted to the terrain, intersected the main road.
Building remnants belong to the Hellenistic era, which is the last period of the city's prosperity. The residential development is amphitheatrical due to the inclination of the terrain and to the building in such way so there was a view of the sea.
Few private houses have been excavated organized in neighborhoods, mainly in the eastern part of town. The habitation sites were built around a closed courtyard and beneath it was a tank collecting rainwater. Homes had more or less spaces, or were developed vertically with a second floor depending on the social and financial status of the residents.
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