Borussia VfL 1900 Mönchengladbach e.V., commonly known as Borussia Mönchengladbach, Mönchengladbach or Gladbach, is a professional football club based in Mönchengladbach, North Rhine-Westphalia, Germany, that plays in the Bundesliga, the top flight of German football. The club has won five League titles, three DFB-Pokals, and two UEFA Europa League titles. Borussia Mönchengladbach were founded in 1900, with its name derived from a Latinized form of Prussia, which was a popular name for German clubs in the former Kingdom of Prussia. The team joined the Bundesliga in 1965, and saw the majority of its success in the 1970s, where, under the guidance of Hennes Weisweiler, they captured five league championships with Die Fohlen team; a term coined as the squad were young with a fast, aggressive playing style. Mönchengladbach also won two UEFA Cup titles during this period. Since 2004, Borussia Mönchengladbach have played at Borussia-Park, having previously played at the Bökelbergstadion since 1919. Based on membership, Borussia Mönchengladbach is the fifth largest club in Germany, with over 75,000 members. The club's main rivals are FC Köln, against whom they contest the Rheinland Derby.