As a Biosphere Reserve and UNESCO World Heritage Site, Glacier Bay National Park protects a unique ecosystem of plants and animals living together in an ever-evolving glacial landscape. Hold your breath and wait in expectation and wonder as a monumental chunk of ice splits off a glacier crashes through the silence into the sea? The thunder and power of impact shoots water hundreds of feet into the air. Adjust the focus on your camera and wait for it all to happen again. Glacier Bay has more actively calving tidewater glaciers than anyplace else in the world.