Abstract
This article is based on a Finnish study where the traffic effects of a roundabout were investigated by Leif Beilinson and Risto Kulmala. The project was performed by the Technical Research Centre of Finland (VTT) and commissioned by the Finnish National Road Administration (FinnRA). The study involved a before-and-after testing arrangement at a four-way junction of two highways in the built-up area of Lammi. (Author/publisher)