But of course the number of cars isn't the only issue. It's the number of cars plus the terrible weather that makes the ski traffic so bad. If it is sunny and dry traffic moves a lot better than if it's dark and snowy.
Ski traffic jams on Interstate 70 are a perennial complaint from people in Denver. But the Colorado Department of Transportation says the ski jams are something of a myth and that the highway is actually more congested in summer.
The department says that traffic data show the busiest month of the year at the Eisenhower Tunnel for the past few years has been July.
UPDATE: Denver Post link deleted.