Unlike railroad suburbs, which tended to form in pockets around stations along the interurban line, streetcar suburbs formed continuous corridors stretching outwards from city cores. The streetcar lines themselves were either built on roads that conformed to the grid, or on former turnpikes radiating in all directions from the city, sometimes giving such cities a roughly star-like appearance on maps. Along the lines, developers built rectangular "additions" with homes, usually on small lots, within a five- to ten-minute walk of the streetcar. These were essentially built on the grid plan of the older central cities, and typically spread out in between streetcar lines throughout a city.