To improve safety for users of the Tiburon Boulevard and Greenwood Cove/Blackfield intersection in Tiburon, Marin's first "bike box" has been installed in conjunction with several other intersection improvements.  The project was a partnership between the County, Tiburon, and Caltrans, providing better and safer connections across Tiburon Boulevard (State Highway 131) between the neighborhoods on the north side, including Bel Aire school, with the east-west bicycle and pedestrian connector route for the Tiburon peninsula.  

A bike box provides a dedicated space at the intersection for cyclists to wait for a green signal and which puts them in clear view of motorists to avoid conflicts and collisions.  The significant number of cyclists using this intersection has resulted in queueing in vehicle lanes and confustion for motorists with some cylists' turning movements because of the lack of dedicated turn signals for the side streets.  The Town of Tiburon has more information on the bike boxes and how they work availalble here .