Pacific Northwest Indians preserved centuries of history through stories, including Columbia River Gorge traditions about a natural stone bridge that once spanned the river and linked peoples on the north and south banks. Contemporary geologists agree that about 500 years ago the unstable north side of the Gorge collapsed into the river, creating this crossing. The river later broke through the dam, leaving roaring whitewater rapids that became known as the Cascades of the Columbia. The massive landslide is difficult to recognize from the ground but clear from the air, and it narrowed the river's channel and pushed its course south. In tribal storytelling traditions, legends recounted relatively recent events in realistic terms, and some tell how the jealous brothers Wy’east, Mount Hood, and Klickitat or Pab-toe, Mount Adams, dammed the river with fire and rocks while fighting over Loo-wit, Mount Saint Helens.