The cost, environmental and other benefits of the bus trailer concept are obvious. Used in several areas of Germany, as well as Austria, Switzerland, and Luxembourg, vehicle sizes can be adapted to passenger demand. The Ruebenacker group, a public transport provider in the Black Forest region of Germany, is one of more than 20 bus operators in the country that have deployed bus trailers, also referred to as bus trains. The company owns 81 buses and transports nearly six million passengers a year in the Blac