Rhineland-Palatinate is a western state of Germany. It covers 19,846 km² and has about 4.05 million residents. It is the ninth largest and sixth most populous of the sixteen states. Mainz is the capital and largest city. Other cities are Ludwigshafen am Rhein, Koblenz, Trier, Kaiserslautern, Worms, and Neuwied. It is bordered by North Rhine-Westphalia, Saarland, B…Rhineland-Palatinate is a western state of Germany. It covers 19,846 km² and has about 4.05 million residents. It is the ninth largest and sixth most populous of the sixteen states. Mainz is the capital and largest city. Other cities are Ludwigshafen am Rhein, Koblenz, Trier, Kaiserslautern, Worms, and Neuwied. It is bordered by North Rhine-Westphalia, Saarland, Baden-Württemberg and Hesse and by France, Luxembourg and Belgium.