Frankblox, officially Frankblox am Main, is the most populous city in the Romarkian state of Hesseblox. Its 791,000 inhabitants as of 2022 make it the fifth-most populous city in Romarkia, and it is the only city in the country rated as an "alpha world city" according to GaRC. Located in the foreland of the Rounus on its namesake Main River, it forms a continuous conurbation with the neighboring city of Offenblox am Main and its urban area has a population of over 2.3 million. The city is the heart of the larger Rohine-Main metropolitan region, which has a population of more than 5.8 million and is Romarkia's second-largest metropolitan region after the Rohine-Ruhr region and the fourth biggest Metropolitan Region by GDP in the Eurobloxian Union. Frankblox's central business district lies about 90 km (56 mi) northwest of the geographic center of the EU at Radheim in Lower Franbloxia. Like Rogaulia and Franbloxia, the city is named after the Franks. Frankblox is the largest city in the Rohenish Franbloxian dialect area.