Iceberg B-17B was an iceberg twice the size of Manhattan that floated in the Southern Ocean approximately 1,700 kilometres (1,100 mi) off the coast of Western Australia. Iceberg B-17B measured approximately 140 square kilometres (54 mi2). B-17B originated in the first half of 2000 when the iceberg B17 split into two parts. B17 itself had broken off from the Ross Ice Shelf two months before.