ancient abandoned cities

Both cards sent from Luca (Ascoli Piceno - italy)
Su Nuraxi - Barumini
Village in the middle of Sardinia, built between XIII and VI century AD. The most ancient structure is a three-storey tower. Function unclear, maybe military or maybe as temple or meeting point for social decisions. The site was discovered in 1950's and witnesses the anciety of sardinian civilization. It's UNESCO and was also occupied by Romans before being finally abandoned in VI century AD.

Petra - Jordan
rock-cut city between the Red and the Dead seas, of prehistoric origins and protected by deserts. Occupied by Bizantine and Romans (they are everywhere!), has an ingenious water management system allowing life in such an arid area. Became of key commercial value as caravan centre, as it as at the crossroads between Africa, Asia and Europe.