Safe Cycling on Boulder County Roads

Three Feet to Pass Law

Colorado law states drivers must give cyclists 3-feet of room when moving past them. That’s 3-feet from the widest point of the vehicle, which is typically the side mirrors, but can also be a trailer in tow. Motor vehicles should attempt to give cyclists as much room as possible when passing.

Vehicles can cross a double-yellow line to pass a cyclist. The yellow lines advise drivers that they should stay in their lane due to a reduced line of sight, whether it be due to a curve ahead or the road is moving over a hill. It is not against the law to cross the double-yellow line to pass a cyclist, but you must be safe when doing so.

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2525 13th St.
Boulder, CO 80304

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P.O. Box 471
Boulder, CO 80306