Icebergs in the North Atlantic come from glaciers along the Greenland coast. At 7km per year, the icebergs found off the coast of Newfoundland are the fastest moving in the world. The biggest iceberg ever recorded was 208 miles long and 60 miles wide, a total of 12,000 square miles - that's larger than Belgium.

Of the 40,000 icebergs that calve in Greenland, approximately 800 make it as far south as St John's ( 48 degrees North ). They will be seen in the spring and early summer between 75 degrees North and 40 degrees North.

The icebergs off the Newfoundland coast this year were calved more than a year ago. The ice that produced them may be more than 15,000 years old icebergs formed when a glacier advances into the sea and pieces of it break off.

Often eighty-five per cent of the berg is under water. Tiny air bubbles give the iceberg its white colour. The weight of icebergs varies from the very large, ten million tonnes, to the growlers which are the size of grand pianos. The average weight of a Grand Banks iceberg is 1-2,000 tonnes. This is about the size of a fifteen-storey building.

The largest iceberg recorded in the Northern hemisphere would, at nine billion tonnes, have provided enough water for everyone in the world to drink a litre a day for four years.

The frozen water that makes an iceberg is fresh water. The temperature inside an iceberg is around -15 C. At the surface, the temperature is about O deg C.