of the City of Las Vegas. I see numerous "open" spaces and suspect that they are unicorporated area of Clark County. Not being familiar with Nevada annexation laws, I don't know how they are kept out of the City. Perhaps they are Federal areas, or privately held land or even land that the City does not want responsibility for. I believe one of the bigger tracts is Summerlin

Link here: http://major.lasvegasnevada.gov/website/clvcamps/viewer.htm

Jim