To give you some comparison, tabular icebergs average about 100-160 feet in height above the water. The federal building in Juneau is about 120 feet high. Realizing that eighty percent of the mass of icebergs lies below the surface of the water, and that they can roll without notice, we had no qualms about staying clear. There are three categories of floating ice in Antarctica. The largest and most well known are the Tabular Icebergs.
Tabular icebergs are pieces of the ice shelf that have broken away.
They range in size from a few hundred feet across to upwards of seventy miles long. They can be recognized by their flat tops. Bergy Bits form from pieces that have broken off tabular icebergs or when tabular icebergs collide. Smaller Bergy Bits are about the same size as a small car and the larger ones are about the size of an apartment building. The final category is Brash Ice decayed fragments less than seven feet.