Thickest floating ice

Rutford Ice Stream lies along the eastern flank of the Ellsworth Mountains, Antarctica. Radio-echo sounding data obtained in January 1975 by Dr Charles Swithinbank and others of the British Antarctic Survey showed the ice stream is 1,860 m thick at the grounding line, where it starts to float at approximately 77°40’S, 84°15’W, as it flows into the Ronne Ice Shelf. This is the thickest known floating ice in the world.