One piece of the puzzle of Denver's growth as a bike city, explored in-depth in this week's feature, "On a Roll
," is the city's initiative to launch a bike-safety campaign. The effort's been in the works for months, given the rise in collisions between cyclists and cars
. Top city officials met in August to discuss ideas for a marketing push. Here, we take a closer look at efforts in other cities that Denver is looking to for guidance.