State archaeologists have located more than a dozen prehistoric campsites in southeastern Iowa that may date back millennia. Project architect Mike Perry says the initial findings between Burlington and Wapello indicate the artifacts may be eight thousand years old.The items include flint arrowheads, knives and little chips of rock that appear to be the byproducts of stone-tool making. Perry says the excavations have been underway for a few weeks, and are coming to a halt now with the arrival of colder weather.The campsites lie in the path of plans for an expansion to four lanes of U-S Highway 61 in Louisa and Des Moines counties. Construction has been delayed due to state budget cuts. Perry says he hopes the prehistoric campsites can be preserved and further studied.Many American Indian tribes traveled through and lived along the Mississippi River and its tributaries for thousands of years. Perry says there’ve been people in Iowa for ten thousand years.