Wolfsburg is the fifth largest city in the federal state of Lower Saxony, located on Aller river, about 230 km. west of Berlin. It is best known for having the headquarters of the famous German car manufacturers Volkswagen, currently the biggest car assembly plant in the world. Due to its relevance in the history of the legendary German car brand, it also has an outdoor theme park dedicated to the main brands of the Volkswagen group: Volkswagen, Audi, SEAT, Škoda, Lamborghini, Bentley, Bugatti and Porsche. It is also famous for hosting the Wolfsburg Challenger, a tennis tournament held every year since 1993, and for also being the hometown of the homonymous football team.