The urban buses in Offenburg are known locally as "key buses". In a reflection of the motto that "key buses open up the whole town to you", the bus has gained the wholehearted acceptance of the local population and forms the backbone of Offenburg's local public transport system. State-of-the-art and, since very early on, extremely environmentally compatible regular-service buses provide an extensive network that covers the whole city region and even extends into the "Cappuccino Mile", as the city's central pedestrian shopping area is known. On 17 September 2012 the cleanest buses in the history of Offenburg to date were presented to the public: two Mercedes-Benz Citaro G BlueTec Hybrid models.
In the presence of the Minister of Transport for the state of Baden-Württemberg, Winfried Hermann, and the Mayor of the City of Offenburg, Edith Schreiner, the vehicles were handed over by Tammo Voigt, Head of Public Transport Fleet Sales at Mercedes-Benz Buses, to Johannes Müller, representing the Board of Management of the local operating company, the "Südwestdeutsche Aktienverkehrsgesellschaft" (SWEG, or German Transport Operating Company of Southwestern Germany. "As the local transport company for Offenburg we take very seriously our commitment to planning and operating in a way that is environmentally responsible.We are proud to be able to fully integrate such significant key technology into our regular transport operations", said Johannes Müller.