The Callanish Stones are a group of standing stones located on the Isle of Lewis in the Outer Hebrides of Scotland. Dating back to around 3000 BC, these ancient stones are arranged in a circular pattern and are believed to have been used for ceremonial or astronomical purposes. The site consists of a central stone circle surrounded by several other stone alignments. The Callanish site is one of the most significant prehistoric monuments in Scotland and attracts many visitors each year. It is often compared to other famous stone circles, such as Stonehenge, due to its historical and cultural importance. The stones are made of local gneiss rock and vary in height, with the tallest stone reaching about 4.5 meters.