A new developer has a unique idea to put a twist in your retirement lifestyle. River Cities plans to launch a floating retirement condominium community that will travel over 6,600 miles of river and inland waterways throughout the United States. Imagine a lifestyle where you wake up every morning in a new city or along a new bend in one of the country’s beautiful networks of rivers. The idea is the brainchild of David Nelson and if everything works out according to his plan, his boat, The Marquette, will set sail a couple years from now.