FRISCO - The roads were slick and snowpacked, and blizzard-like conditions limited visibility when cars and trucks began sliding out on Interstate 70 Monday afternoon.
As the first cars collided, those that followed slid and slammed into the growing wreck, while others went off the road into snowy shoulders and medians.
A reported total of 54 vehicles were involved in two pile-up crashes - one eastbound, one westbound - that closed I-70 for hours between Vail Pass and Georgetown.
"It is a mess," Colorado State Patrol trooper Nate Reid said Monday. "They have slide offs and crashes in both directions."
Five people were hospitalized with injuries from the crash, but only one suffered serious injuries and had to be transported to a Denver-area hospital, according to statements from the Summit County Sheriff's Office.
The first accident, which ultimately involved 25 vehicles and 27 people, began just after 1 p.m. on the westbound highway lanes near the Silverthorne exit. Just hours later, drivers on the eastbound side of the interstate between the two Frisco exits crashed in a second pile-up accident that involved 29 vehicles.
All three of the injuries occurred in the first crash. The individuals involved were treated at St. Anthony Summit Medical Center.
The Outlets at Silverthorne and 1stBank in Frisco offered up space for people involved in the crashes to warm up while tow trucks were removing vehicles from the wrecks, but employees at the bank said no one ever arrived.
Authorities could not confirm Monday what caused either crash, but said vehicle speeds and the weather were likely factors in both.
The highway had reopened in both directions by 5:30 p.m.
Blizzard-like conditions continued throughout most of the day Monday, clearing out only in the late afternoon.