MANKATO-September 19, 2012-(KMKO)-The first of three roundabouts will open to traffic in Mankato next week.  MnDOT officials want drivers to be aware of some basic rules when encountering a roundabout.  Be prepared to drive slowly, no more than 15 to 20 miles per hour.  As always, yield to pedestrians, and don't try to pass another vehicle in the roundabout.  Watch the signs for directions.  To learn more, visit the web at www.dot.state.mn.us/roundabouts.