According to EN 1991-1-4, Table 4.1.
| № | Terrain category | Description |
|---|---|---|
| 0 | 0 | Sea or coastal area exposed to the open sea. |
| 1 | I | Lakes or flat and horizontal area with negligible vegetation and without obstacles. |
| 2 | II | Area with low vegetation such as grass and isolated obstacles (trees, buildings) with separations of at least 20 obstacle heights. |
| 3 | III | Area with regular cover of vegetation or buildings or with isolated obstacles with separations of maximum 20 obstacle heights (such as villages, suburban terrain, permanent forest). |
| 4 | IV | Area in which at least 15 % of the surface is covered with buildings and their average height exceeds 15 m. |