Early San Francisco
The 1906 San Francisco earthquake and fire rivalled the Chicago fire of 1871 in the annals of urban disasters in America. Large conflagrations were common in cities of the nineteenth and early twentieth centuries, which were often crowded and lacked the sophisticated safety consciousness of today. However, the totality of destruction caused by these two disasters was extraordinary, comparable only to that of the southern cities razed during the Civil War. Even that comparison pales since those cities were destroyed before the period of phenomenal growth of American cities that would mark the latter half of the century.
By contrast, 1906 San Francisco was already a booming metropolis -- as was Chicago in 1871, albeit one built of wood -- having undergone a tremendously prosperous post-Civil War period of growth and development. Also, the destruction of the Southern cities during the Civil War was relatively prolonged, eventually even expected and inevitable. Unlike San Francisco and Chicago, their destruction did not occur at a precise, unexpected moment -- a moment when the old city is doomed to rubble and ash and a new era of reconstruction is forced upon a population that had only the day before gone about its business in typical fashion.