"The Hills" introduced us to Colorado-bred, fashion school drop-out Heidi Montag when it took to the airwaves in 2006. The past four years have documented big changes for Heidi - the end of friendships, a marriage to Spence and many more. Take a look back at Heidi before we say good-bye. / Joe Kohen/ Getty Images

The Evolution Of: Heidi Montag (15)