Great Blue Hole
The Great Blue Hole is a giant marine sinkhole off the coast of Belize. It lies near the center of Lighthouse Reef, a small atoll from the mainland and Belize City. The hole is circular in shape, across and deep. It was formed during several episodes of quaternary glaciation when sea levels were much lower. Analysis of stalactites found in the Great Blue Hole shows that formation took place 153,000; 66,000; 60,000; and 15,000 years ago. As the ocean began to rise again, the cave was flooded. The Great Blue Hole is a part of the larger Belize Barrier Reef Reserve System, a World Heritage Site of the United Nations Educational, Scientific and Cultural Organization (UNESCO).
Blue Hill (CDP), Maine
The Blue Hill CDP consists of the main village within the town of Blue Hill. The CDP is located at the geographic center of the town, surrounding the head of Blue Hill Harbor, an arm of Blue Hill Bay. The CDP extends south along Route 175 as far as Bragdon Brook, just north of Blue Hill Falls; southwest along Routes 15 and 176 as far as Grindleville Road; west along Route 177 (Union Street) to Field House Lane; northwest along Route 15 past Mountain Road to the southern slopes of Blue Hill; northeast along Route 172 past Mountain Road; and east along Route 176 to Peters Cove and Little Peters Brook. The summit of Blue Hill is just outside the CDP to the north.