" Though it still needs to
be confirmed, this canyon system looks to be more than
600 miles long and as deep as half a mile in places. (The
Grand Canyon, by comparison, is 277 miles long and up
to a mile deep.) The canyons appear to connect to a
subglacial lake that's nearly 800 square miles in area,
.."
http://m.newser.com/story/218959/vast-find-made-in-unknown-region-of-antarctica.html?utm_source=happyhour&utm_medium=email&utm_content=2833320&utm_campaign=20160114
