During the 1950's and 1960's roundabouts were almost abandoned as a traffic regulation form in Denmark. In 1975 the rule of entry into a roundabout was changed into the "yield at entry" rule. From about that time roundabouts have been constructed in many places. Two types are used: 1) roundabouts used as a means of improving flows through an intersection; 2) roundabouts used as a speed reducing measure, primarily in housing areas. Design standards are being developed for both types of roundabouts (Vejdirektoratet (1989): Byernes Trafikarealer, Preliminary version of recommended design standards for urban roads in Denmark. In Danish). The design of speed reducing roundabouts necessarily differs from flow improving roundabouts. Speed measurements on vehicles approaching, going through and leaving the two types of roundabouts are scheduled to be completed by June 1990. A major problem at Danish roundabouts is the cyclists. The majority of personal injuries occur to cyclists. The dominant accident type is an entering car hitting a circulating cycle. For this reason roundabouts are only slightly safer than other intersection types. Different layouts are being tested in order to improve the situation.
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