 Henrico was the third Virginia county (after Arlington and Fairfax counties) to be affected by a state law that prohibits the creation of any new towns or cities within the boundaries of a county with a population density of 1,000 or more per square mile.Prior to 1870, the Town and later City of Richmond was located within Henrico County.Under a new Virginia state constitution in 1870, and as further clarified by rewritten one in 1902, Richmond became an independent city.