Isn't there evidence of one of the largest river floods ever to occur due to a massive slide blocking the Columbia?There are ghost towns in the cascades not because they lost economic viability, there were too many floods and landslides that they just became cut off from the rest of the world. I've seen a handful of pretty big rock slides and the aftermath of a huge one that must have been only a few days old. The most dangerous thing out here is the ground.