This reform abolished the traditional counties (Danish plural: amter, singular: amt) and created five regions.

Denmark's largest lake, Arresø, lies 43 kilometres (27 mi) northwest of Copenhagen.

Geologically, the region lies in the northern part of Denmark, which is rising, or sinking the least, due to post-glacial rebound, turning former inlets and bays into lakes.

[5] (The land is rising by 9 millimeters every year in Furuögrund [sv], the northeastern part of Skellefteå Municipality, north of Kvarken.)

Because of the mobility of the sand dunes, forests have been planted along the coast of Kattegat in the municipalities of Helsingør, Gribskov, and Halsnæs.

The land area of east Denmark (east of the Great Belt) is approximately 9,622 km2 (3,715 sq mi) and is set to increase due to housing projects in the north of Copenhagen Municipality, and also due to new bridges and tunnels being added, such as the Fehmarn Belt Fixed Link and other traffic infrastructure projects.

The gross domestic product (GDP) of the region was €122.2 billion in 2018, accounting for 40.6% of Denmark's economic output.

GDP per capita, adjusted for purchasing power, was €50,000 or 166% of the EU average (excluding the United Kingdom) in the same year.