Nitro is a city in West Virginia, along the Kanawha River. Most of the city lies in Kanawha County, with the remainder in Putnam County. The population was 6,824 at the 2000 census.
Nitro was incorporated in 1932 by Circuit Court.
The name Nitro derives from nitrocellulose. The Nitro area was to be the American ammunition production facility during World War I. Its name was selected by the United States government because of the establishment there, during World War I, of a large federal plant for the manufacture of explosives. The chemical plants in the area were able to fulfill this function during World War II, on a lesser scale. The city is known as the "Magic City," or a "Living Memorial to World War I."