Map visualisation service (WMS) of the dataset: Urban area from Urban Unit according to INSEE 2008 in the Somme

The concept of urban unity is based on the continuity of the building and the number of inhabitants. An urban unit is a municipality or a set of municipalities with a continuous built-up area (no cut of more than 200 meters between two buildings) that has at least 2,000 inhabitants.If the urban unit is located in a single municipality, it is called an isolated city. If the urban unit extends over several municipalities, and each of these municipalities concentrates more than half of its population in the continuous built-up area, it is called a multi-communal agglomeration. The concept of urban unity is based on the continuity of the building and the number of inhabitants. An urban unit is a municipality or a set of municipalities with a continuous built-up area (no cut of more than 200 meters between two buildings) that has at least 2,000 inhabitants.If the urban unit is located in a single municipality, it is called an isolated city. If the urban unit extends over several municipalities, and each of these municipalities concentrates more than half of its population in the continuous built-up area, it is called a multi-communal agglomeration.城市单元（urban unit）的概念以建筑连续性与居民数量为核心判定依据。城市单元指具备连片建成区（两栋建筑之间的间隔不超过200米）且常住人口不少于2000人的单个市镇或多个市镇的集合。若该城市单元仅坐落于单个市镇范围内，则称为孤立城市；若城市单元跨越多个市镇，且每个涉及市镇均有超过半数的人口聚居在该连片建成区中，则称之为多市镇集聚区（multi-communal agglomeration）。 城市单元的概念以建筑连续性与居民数量为核心判定依据。城市单元指具备连片建成区（两栋建筑之间的间隔不超过200米）且常住人口不少于2000人的单个市镇或多个市镇的集合。若该城市单元仅坐落于单个市镇范围内，则称为孤立城市。 若城市单元跨越多个市镇，且每个涉及市镇均有超过半数的人口聚居在该连片建成区中，则称之为多市镇集聚区。