The degree of urbanisation is applied in a two-step process: First the grid cells are defined based on density, contiguity and population size. Subsequently small spatial units are defined based on the type of grid cells most of their population resides in.

The dataset is based on 2011 population grid of GEOSTAT and the European Settlement Map 2012 from Copernicus, identifies six classes: 1) cities, 2) towns, 3) suburbs, 4) villages, 5) dispersed rural areas and 6) mostly uninhabited areas.

The original degree of urbanisation has three classes (level 1). It identifies individual cities, but does not provide any distinctions in the other two degrees. he global commitment should define not just cities but other settlements as well. So, the degree of urbanisation was refined (level 2) to also identify smaller individual settlements. The approach was based on population and population density into a grid concept.

(1) City has an urban centre with a population over 50,000.

(2) To define the towns and the suburbs, three types of grid cells were defined.

(2.1) A dense urban cluster consists of contiguous cells with a density of at least 1,500 residents per sq km and a population between 5,000 and 50,000 in the cluster

(2.2) A semi-dense urban cluster is an urban cluster (see above) located more than 2 km from a dense urban cluster or an urban centre (distance is measured between the edges of the clusters)

(2.3) Suburban cells are the remaining cells in an urban cluster, i.e. not part of a dense or semi-dense urban cluster

(3) Rural areas were broken down into:

(3.1) A rural cluster consists of contiguous cells with a density of at least 300 residents per sq km and a population between 500 and 5,000 in the cluster.

(3.2) Low density rural grid cells are cells with a density between 50 and 300 inhabitants per sq km

(3.3) Very low density rural grid cells are the remaining rural grid cells, i.e. those with a density of less than 50 inhabitants per sq km

The final legend of the dataset is:

• Urban centre with a population over 50,000 (raster value = 30).

• Towns have the majority of their population living in a dense or semi-dense urban cluster (raster value = 22).

• Suburbs have the majority of their population living in suburban cells (raster value = 21).

• Villages have the majority of their population living in a rural cluster (raster value = 13).

• Dispersed rural areas have the majority of their population living in low density rural grid cells (raster value = 12).

• Mostly uninhabited areas have the majority of their population living in very low density rural grid cells (raster value = 11).