Early examples of the articulated bus appeared in Europe in the 1920s. In 1938, Twin Coach built an articulated bus for the city of Baltimore; this bus, which had four axles on a 47 ft (14.33 m) long body, was only articulated in the vertical direction to accommodate steep grades. 15 examples of the "Super Twin" were built in 1948, but it was not developed further.[2] According to contemporary coverage, the Super Twin had a capacity of 58 seated and 120 total, with a weight of 27,500 lb (12,500 kg).[3]