As urban bicycling becomes more common, new types of infrastructure are being invented to help bikes safely mix with cars. The latest innovation is what’s called a “two-stage bike box.” Arlington is proposing one for this particularly confusing intersection:


Image by Arlington County.



This intersection, of Wilson, Washington, and Clarendon Boulevards, is often referred to as “Clarendon Circle,” because it used to be one. During the 20th Century the circle was removed and the intersection widened. Now Arlington wants to make it safer for pedestrians and bicyclists.

There are a lot of interesting things going on with this plan, but the most interesting is the bike queuing zone in the lower right corner of the intersection. The idea is that cyclists hoping to cross Washington Boulevard in order to move east along Clarendon Boulevard will have a dedicated and safe place to wait, separated from both cars and pedestrians.

The two-stage bike box is similar to regular bike boxes, except that it’s located in a reserved corner of the intersection rather than between the crosswalk and stopping stripe.

A normal bike box behind the crosswalk on either southbound Washington Boulevard or eastbound Wilson Boulevard would be less versatile, because it would only benefit cyclists on that one street. The two-stage box helps people moving onto Clarendon Boulevard from both Wilson and Washington, which is why it’s a clever innovation at this location.

There are a few two-stage bike boxes in Portland and New York, but they use a somewhat different design. Clarendon Circle will be the first implementation of this idea in the DC area, and will also be the first-anywhere use of this particular design, which hugs the curb in an inverted nub.

Cross-posted at BeyondDC.