The sign can freeze the heart: "Chains Required."
But it is a fact of life in winter that mountain passes will occasionally get enough snow to make the roads slippery, requiring a little more than the usual tires to get through.
The transportation departments in both Oregonand Californiawork hard to keep the mountain passes open, but they present challenges.
Gary Leaming from ODOT explains how the two states coordinate efforts, and how they deploy crews and equipment in winter storms. No chains required to listen.