In recent years many cities have made a commitment to promoting bicycle commuting and safety by building bike trails, lanes, and paths.
Although this is a great idea that has made bicycling safer in many cases, many bicyclists and drivers continue ignoring bicycle safety rules such as not wearing a helmet, something that local governments can do little to change beyond constant reminders with safety warning signs. Bicycle lanes are sometimes assumed to be a sure sign of immunity from harm by bicyclists, giving them the freedom to do anything they want and disregard auto traffic even as it passes near bike lanes.
Marked bike lanes are no excuse to stop monitoring the surrounding traffic situation, as drivers unfamiliar with the area may be startled to find a bike lane. In heavy traffic areas it may be best to take the quiet residential street a block or two away, instead of enduring traffic noise and exhaust fumes which may be harmful, plus drivers quickly turning corners without noticing bicycles.
When crossing busy intersections with electric walk signals, it may be safer to cross there instead of a block down where there is no traffic light, as bicyclists may have to wait a long time for traffic to clear, plus the risk of a car pulling out suddenly from a parking lot or side street.
When pedaling at dawn or evening, having a rear flashing red light mounted under the seat, plus either a reflector or light on the front handlebar is a must. A bicycle enveloped in darkness is an invitation to lose life or limb, and the cyclist has to make an effort to stand out with bright clothing and helmet.