Sankaty Bluff

Sand, gravel and boulders laid down by the last glacier during the Wisconsinan Glacial Stage was not the first layer of foundation for Nantucket; an ocean bottom created during the Sangamonian Interglacial Stage and another pavement of glacial material during the Illinoian Glacial Stage are also underneath us. The only place to see all three distinct layers up close in an exposed cross-section view is Sankaty Bluff. On this hike, we’ll walk south down the beach from the Hoicks Hollow Road public way to where these layers are visible, learn about how they were formed and how they are part of Nantucket’s geological past.