What is the valley of ashes?

First introduced in Chapter 2, the valley of ashes between West Egg and New York City consists of a long stretch of desolate land created by the dumping of industrial ashes. It represents the moral and social decay that results from the uninhibited pursuit of wealth, as the rich indulge themselves with regard for nothing but their own pleasure. The valley of ashes also symbolizes the plight of the poor, like George Wilson, who live among the dirty ashes and lose their vitality as a result.