The Snake River Canyon between Alpine and Jackson Hole, Wyoming is notable for its unstable mountainslopes. This mountain range is very prone to earthflows, one reason the Snake River Range is not cut up with dirt roads. The whole place would come down. However, a U.S. Highway has followed the canyon for perhaps 75 years, and slides over it are common. This spring saw a monster slide. It blocked traffic for about two weeks. Clearing the highway was pointless because it just kept sliding. The daily traffic of workers from Star Valley, Wyoming to Jackson was blocked, causing them to drive perhaps a hundred miles extra over Teton Pass, and causing a traffic problem there.
WyoFile posted a YouTube time lapse-video of the slide. It should be shown to a geology class, or better, to highway builders.
