In this talk we apply percolation theory to the road network of the UK. We obtain a multiplicity of transitions, indicating a hierarchical organisation of the urban system. The lower transition reveals the core of cities, and at larger thresholds regional fractures of Britain appear. We analyse the properties of the clusters emerging at the different distance thresholds through their multifractal spectrum, and observe that this reaches a maximum at the point where the correlation between city boundaries and satellite images is the largest.