The goal is to transform Union Station into a traveler and visitor's venue that tops the highly successful retail and food and beverage offerings at Union Station in Washington, D.C., as well as at highly touted rail depots in Seattle and Denver, said Paul Sanders, Amtrak senior manager of facilities management at Chicago's Union Station. To that end, the national passenger railroad is soliciting proposals from investors and businesses to bid on up to 25,000 square feet of potentially stunning retail rental spaces, according to Amtrak, which owns the building.