While the Grand Canyon is largely considered to be the planets biggest natural rift, scientists discovered another trench on Antarctica that could rival one of America's mightiest natural features. The unnamed canyon was found during a 2010 expedition and extends 100 kilometres, is more than 9 kilometres wide and reaches depths of more than 1,6 kilometres. Scientists speculate that it could be even larger, but further exploration is required to learn the true boundaries of this massive rift.