Anasazi Haven is a ruin found in Canyonlands national park that dates to the 900s according to the park service documentation found at the site.  As I sat there waiting for the lowering of the sun a volunteer archaeologist from Hovenweep national monument hiked into the ruin.  We talked about the dating of the site and concluded that it may have been more to the 400s basket maker type of ruin judging by the nearby cysts and construction of the main ruin.  Dating of these sites is academic, and my interest in them are the aesthetics they afford along with the glimpse into our past.