The Rhine-Main Metropolitan Region, often simply referred to as Frankfurt Rhine-Main, Frankfurt Rhine-Main area or Rhine-Main area, is the second-largest metropolitan region in Germany after Rhine-Ruhr, with a total population exceeding 5.8 million. The metropolitan region is located in the central-western part of Germany, and stretches over parts of three German states: Hesse, Rhineland-Palatinate, and Bavaria. The largest cities in the region are Frankfurt am Main, Wiesbaden, Mainz, Darmstadt, Offenbach, Worms, Hanau, and Aschaffenburg.

Darmstadt is a city in the state of Hesse in Germany, located in the southern part of the Rhine-Main-Area. Darmstadt has around 160,000 inhabitants, making it the fourth largest city in the state of Hesse after Frankfurt am Main, Wiesbaden, and Kassel.