Birmingham is a young city, having grown rapidly as a result of the Industrial Revolution starting in the 18th century. There are very few buildings remaining in Birmingham prior to this. Further loss has been demonstrated through the effects of war and redevelopment, especially following World War II. Industrialisation and planning policies have also led to Victorian buildings being demolished but the prosperity brought with it led to some of the city's grandest buildings being constructed, although in turn many of these are being or have been demolished. Industrialisation and the growth of the city led to its boundaries expanding and the city acquired other forms of architecture. As of April 2006, there are 1,946 listed buildings in Birmingham, thirteen scheduled ancient monuments and 27 conservation areas.