They live on top of meteor craters. In the 10th century, a community of Greek Orthodox monks was looking for a place to live their faith serenely and isolate themselves from the rest of the world. They had the idea of ​​settling at the top of several meteorite craters, located in northern Greece. The Meteors form a set of sandstone blocks that were formed under the sea 30 million years ago. In the 16th century, there were 24 monasteries, today only six remain. The Monastery of the Transfiguration of the Savior is the best known of them. It is also the highest perched, it culminates at 534 meters above sea level. The Meteora site has been a UNESCO World Heritage Site since 1988.