this 600 million year old gneiss rock in rockefeller state park preserve is one of the largest glacial erratics in the us

600 age almost america american ancient circumference countryside education environment erratic erratics exploration geologic geology glacial glacier gneiss high historic history ice landmark largest learning million natural nature new northeast old one outdoor outdoors park pleasantville prehistoric prehistory preserve recreation retirement retro rock rockefeller scenery scenic state states stone this tourism travel united usa vacation year york