The Grand Banks of Newfoundland are located off the southeast coast of the province. In this area, the continental shelf is exceptionally wide. The Grand Banks is a 730-kilometre stretch of shallow continental shelf that extends as far as 480 kilometres from the coast. These banks are submarine plateaus that rise from the underlying continental shelf, to just 25-100 metres below the ocean surface. The average depth of these banks is around 150 metres, but there are many troughs in the shelf floor of glacial origin that are as deep as 200 metres or more.
These surface waters - in fact, the Grand Banks are the best place to spot these enormous chunks of glacial ice as they drift down from Greenland. The cold Labrador Current runs over the Grand Banks, and when warm air passes over this water, a dense fog forms. The fog, shallow waters and drifting icebergs make navigation difficult in this region.