Ancient civilizations showcased their ingenuity by constructing stunning structures on natural rock faces and cliffs around the world. Examples include the Cliff Palace in Colorado, the Necropolis of Pantalica in Sicily, the Cliff of Bandiagara in Mali, and the Paro Taktsang Monastery in Bhutan. These structures were built in response to changing environmental conditions and served various purposes such as dwelling places, tombs, and religious centers. They continue to captivate visitors with their architectural beauty and historical significance.