Cities can be planned and designed to reduce their effect on biodiversity loss and may even be able to sustain biodiversity levels in some instances, due to ‘beta-diversity’. The heterogeneity of metropolitan regions can be expected to have a strong impact on beta-diversity. Tools such as landscape characterization can assist in the understanding of betadiversity in metropolitan regions by mapping the extent and configuration of beta-diversity conditions, in particular microhabitats and habitat mosaic configurations. A new tool for landscape characterization of metropolitan areas (MLC) trialled on the Rotterdam metropolitan region generated thirty-six distinctive landscape types - twelve continuous and twentyfour discontinuous (hybrid) types. Hybrid landscape types are present throughout the whole of the territory and are potential micro-habitats for flora and fauna. The interrelationship of continuous and discontinuous (hybrid) landscape types are potentially valuable habitat mosaic configurations.