Over a century ago, Midwesterners trekked by wagon to summer at Lake Okoboji. They still travel to northwest Iowa today, drawn to the deep, sparkling natural lake set amid table-flat cornfields. The Iowa Great Lakes-East and West Okoboji and Big Spirit-boast excellent fishing for walleyes, smallmouths, northerns, muskies, and perch. The towns of Okoboji, Spirit Lake, and Arnolds Park feature water slides, parasailing, scenic cruises, and a wooden roller coaster at the oldest amusement park west of the Mississippi. Best souvenir: T-shirt from the mythical University of Okoboji. 800-270-2574; www.vacationokoboji.com.