What is the Valley of Ashes, literally? What else might it represent?

The Valley of Ashes make up the undesirable, poorer section between the Eggs and the city. The road from West Egg to New York City exemplifies decay. It is a "valley of ashes," a place of uninterrupted desolation. The novel's only non-wealthy characters live in the valley of ashes; it is the grim underside to the hedonism of the Eggs, and of New York City. George Wilson, Myrtle's dejected husband, seems almost made of ashes: "ashen dust" coats his clothes and his hair. Fitzgerald represents poverty as lying beneath wealth and providing the wealthy with a dumping ground. It is what the wealthy wish to avoid seeing at all costs.