The archaeological complex "Kaleto", treasuring up seventy-centuries-old history, is located in the south-western end of Mezdra, on a high rocky ridge overlooking the left riverside of Iskar.The hill is naturally protected and located in a place where the main roads that have been used since ancient times have crossed to till today.At this crossroads of civilizations, remains have been gathered from all the human history - from the Stone Age to the Middle Ages.The hill over the Iskar River has preserved the traces of 2 consecutively fortified settlements from the end of the stone-copper age (the second half of the 5th century BC) and the transitional period to the Bronze Age (the first half of the 4th millennium BC) , which were destroyed in case of fires. The numerous finds from the excavations of Kaleto unambiguously show that at the end of the Stone Age the settlement near Mezdra thrives as a craft center.