The layout of the Roman and medieval walls have had a profound effect on the development of London, even down to the present day. The walls constrained the growth of the city, and the location of the limited number of gates and the route of the roads through them shaped development within the walls, and in a much more fundamental way, beyond them. With a few exceptions, the parts of the modern road network heading into the former walled area are the same as those which passed through the former medieval gates.