Columbia subject headings:
Harvard subject headings:
Express highways--Colorado--Vail Pass (Summit County and Eagle County)--Design and construction.
Express highways--Colorado--Vail Pass--Design and construction.
Interstate 70--Colorado--Vail Pass.
Interstate 70.
Roads--Environmental aspects--Colorado--Vail Pass (Summit County and Eagle County)
Roads--Environmental aspects--Colorado--Vail Pass.
Princeton subject headings:
Express highways--Colorado--Vail Pass--Design and construction.
Interstate 70.
Roads--Environmental aspects--Colorado--Vail Pass.