Was at a small damn in Ohio and a Corp of Engineering guy came over and nicely told us it was restricted airspace. Just as he was telling us, a small plane flew low directly over the dam. After an awkward pause, he said they shouldn't be doing that. Anyway, we apologized for not knowing and went to see the ranger. He was baffled as to why the other guy brought us to him and shrugged as if what was he supposed to do. The ranger said paraphrasing, "I would love to have one of those. People have been flying rc craft for decades and no one cared until drones." Then he told us about an rc field about 15 minutes away that is about 100 ft. next to another small dam. He put his hands up and shrugged again. Very cool guy. He took our names and email address and said he'd see if he can get us permission to fly over it. My wife and I are probably on some list now. This is a dam where people can walk over the dam and it is not patrolled on the weekend. I've searched and can't find a restriction. I should stress that it was not an unpleasant encounter. BTW, the few people at the dam were thrilled with the quad, as am I.