In 1956, the largest iceberg on record was sighted by the USS Glacier, a U. S. Navy icebreaker, about 150 miles west of Scott Island in the Southern Hemisphere. It had broken from the Ross ice shelf in the Antarctic. Its size was about the size of Belgium - 208 miles long and 60 miles wide (335 km by 96 km). This record iceberg was many times larger than any seen in the Northern Hemisphere, where the largest iceberg on record was encountered near Baffin Island in 1882. It was 13 km long by 6 km wide, had a freeboard (height above water) of about 20 m, and a mass in excess of 9 billion tonnes. The USS Glacier, commissioned in 1955, was at the time of her construction, the largest icebreaker ever built.«[Image: Iceberg B-19, a more recent huge iceberg that calved in Mar 2000]