The first people to reach North America almost certainly did so without knowing they had crossed into a new continent. They would have been following game, as their ancestors had for thousands of years, along the Siberian coast and then across the land bridge. Once in Alaska, it would take these first North Americans thousands of years more to work their way through the openings in great glaciers south to what is now the United States. Evidence of early life in North America continues to be found. Little of it, however, can be reliably dated before 12,000 B.C.; a recent discovery of a hunting lookout in northern Alaska, for example, may date from almost that time. So too may the finely crafted spear points and items found near Clovis, New Mexico.