Sunday 3/3/2013 at 6:45pm, observed a gold or silver Saturn sedan, MN license plate 837-BJH. Driver was proceeding eastbound, made a U-turn at Fremont heading west, then exited at Humboldt. Not sure if "innocent mistake" or drunk or what. Weather conditions were dry. No matter how innocent the mistake, I'm sure it has happened before and will happen again. Better signage is needed at the 3 at-grade Greenway crossings west of Hennepin Ave (Humboldt, Irving, James).