Onteora Scout Reservation lies withing the Catskill Mountain Range, which formed in the Devonian Period, over 400 million years ago! At this point in geologic history, North America was attached to present day Greenland, the United Kingdom and Scandinavia before tectonic forces separated them to where they are today. The Catskills are predominantly made up of sandstone and shale, sedimentary rocks formed by little particles getting compacted tightly together.