Key West is a city an an island of the same name near the southernmost tip of the Florida Keys in Monroe County, Florida, United States. The city encompasses the namesake island, the part of Stock Island north of US-1 (the Overseas Highway) (east), Sigsbee Park (north, originally known as Dredgers Key), Fleming Key (north), and Sunset Key (west, originally known as Tank Island). Nearby Key Haven (northeast), the part of Stock Island south of US-1 (east) and Wisteria Island, better known as Christmas Tree Island (northwest), are in unincorporated Monroe County. Both Fleming Key and Sigsbee Park are part of the NAS Key West and are inaccessible by civilians.