vistor center or holy grail?

Today we are exploring the locks and dams on the Mississippi River around Molina, IL. To make sure we have all the hot spots in the region, John wanted to check in at the Mississippi River Vistor's Center in town.  HA! Our Garmin takes us right to the Rock Island Arsenal Army Military Base: "You have arrived at your destination." There is a guard shack where John pulls in.  The GI Joe promptly steps out and asks John for his driver's license. Then tells him to "drive over there" when another GI Joe will meet him.  They both have like 25 guns and rifles all over their bodies.  GI Joe 2 tells John to put in another location on his Garmin and sends him on his way.  We go to the next location after twenty five switch backs and dead ends in Molina.  Finally, we go on the last leg of the directions...only to find out we are now heading BACK to the Arsenal on the island but from the east this time. Yep, NO TRESSPASSING. He pulls to the right and sees it "VISITOR CENTER".  He pulls in and goes in. Not the visitor's center.  It's a place to get a permit for every single person in the car to go back to the other entrance and then go into the visitor's center on the base.  WE GAVE UP. 
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