Boat trips are available right up to the base of the glacier. The boat is not allowed to get too close because there is a danger that a large piece of the glacier could break off and damage the boat or worse, a passenger. When a piece of glacier breaks off a deafening bang fills the air like thunder and shards of the glacier can fly off with the speed of a bullet! The enormous pieces of ice sink into the water, leaving behind huge ripples of water like tidal waves on the otherwise glassy lake.