In November 2007, the DARPA Urban Challenge took place on the former George Airforce base in Victorville, California. Within that competition, teams from all-over the world had to demonstrate the autonomous driving capabilities from their robot cars in an urban-like environment. From initially 89 competitors, only eleven qualified for the final event wherein Boss from Carnegie Mellon finally won the race. In this article, a short overview over European's best team CarOLO and its vehicle Caroline within that competition is outlined. Based on the experiences from that competition, remaining challenges for the software engineering are described to realize safer cars in the future.