The Zhiguli are considered the only tectonically active mountains in European Russia, first having formed around 7 million years ago. The summits and other exposed areas of the Zhiguli are composed of limestone and dolomite sediments laid down 230-350 million years ago in the Permian and Carboniferous periods. The slopes of Zhiguli are mostly formed from products of aeration of the Permian and Carboniferous bedrock.