Iowa's landscape has changed dramatically over the past 10,000-15,000 years. Travel through time from the age of the glaciers, through several thousand years of prairie and formation of the world's richest topsoil, to modern agricultural practices today. Prairies and wetlands were integral part of Iowa's history, and we look to them as keys to our future, working together with cropland to maintain the ecological health of our lands and waters. Get Informed. Get Involved. www.waterrocks.org Iowa State University does not discriminate on the basis of race, color, age, ethnicity, religion, national origin, pregnancy, sexual orientation, gender identity, genetic information, sex, marital status, disability, or status as a U.S. veteran.