Cyclists at roundabouts – looked-but-failed-to-see

Drivers can look straight at cyclists and still not “see” them. This is a psychological phenomenon called Inattentional Blindness (aka looked-but-failed-to-see) and is especially prevalent at roundabouts when cyclists have priority.

Poudel and Singleton (2021) did a large literature review of cyclists at roundabouts and they found consistent research results that showed on-road bike lanes within roundabouts lead to “adverse bicycle safety impacts” (even compared to providing no bicycle facilities). However, they found that a separated cycle path reduced crashes by 84% compared to roundabouts with no bike facilities.

We know roundabouts are a wonderful safety feature for most road users, but how do we make them safer for cyclists?
Our colleague Max McCardel runs a whole module in our online Cycling Infrastructure course (course) on roundabout design for cyclist safety, but here’s a snapshot:
???? Physical separation is the gold standard. Check out the Dutch style roundabout designs (designs)
???? Vehicle speed is highly influential on crashes involving all road users at roundabout, including cyclists. So measures to slow vehicle entry and circulating speed are highly beneficial.
???? One lane roundabouts perform better than two (or three) lane roundabouts. Separating cyclists on multi lane roundabouts is even more pertinent.
???? The number of legs entering has an impact on cyclist crashes. If you can consolidate the number of entering legs you’ll reduce risk.
???? Don’t install cycle lanes in an attempt to appease cyclists. They’ll increase crash rates. Instead (if you can’t physically separate) encourage cyclists to position in areas of better sight for approaching drivers, such as claiming the lane (although this is only going to be useful for some of the wide spectrum of people that ride bikes).

Research: Poudel and Singleton, Bicycle safety at roundabouts: a systematic literature review. Transport Reviews, 2021.