Marche region is located in the Central area of the country, bordered by the Adriatic Sea to the east. The capital and the largest city is Ancona. It is dominated by hill country, even mountainous, with river valleys and an often very narrow coastal strip. The highest peaks are in the Apennine range, which runs longitudinally along the region's eastern border. The highest mountain is Monte Vettore (2,476 m als). There are several deep river gorges, like the Furlo, the Rossa and the Frasassi gorges.

The mountains consist quite often of karstified limestone, there are even patches mit gypsum karst. There is only one show cave, but it is really spectacular and a main tourist attraction. It is also the place where the International Show Cave Association (ISCA) was founded. And there are numerous semi-wild caves, and many of them contain cave churches. The area has no active volcanism, but there is volcanic activity in the underground which results in several areas with sulfuric thermal springs. The most famous are at the show cave Grotta Grande del Vento and around the village Acquasanta Terme. The area is also prone to heavy earthquakes, the last one in 2016 rendered several villages uninhabitable.