| Classification | Handbook of Natural Region Divisions of Germany |
|---|---|
| Level 1 Region | Central Uplands |
| Level 2 Region | 24–25, 27–33, 56 → Rhenish Massif |
| Natural region | 32 → Westerwald |
| Natural region characteristics | |
| Landscape type | Mittelgebirge (basement, partly volcanically uplifted) |
| Highest point | Fuchskaute (657.3 m) |
| State(s) | Hesse, North Rhine-Westphalia, Rhineland-Palatinate |
| Country | Germany |
As well as being a low mountain range, the Westerwald is also a natural region in the system of natural regional division of Germany. Within that it is a major unit group with the number "32". According to this system the major unit group of the Westerwald belongs to the basement plate (Grundgebirgsschollenland), which describes the type of mountain-building process by which it was formed. The major unit group extends across the states of Hesse, North Rhine-Westphalia and Rhineland-Palatinate. It is roughly bounded by the valleys of the Lahn (east and south), Rhine and Sieg (via Heller), whereby the hills immediately south of the Heller and Sieg are not considered to be part of it.