This is something that came up last week, and I'm just curious about it. Yes, I'm familiar with the "Photographers Rights" pamphlet even thought I've NEVER had an occasion to use the information in it previously. Basically, the college where I work operates a research facility that happens to be located on the grounds of an Army COE operated lock and dam-specifically the Melvin Price Lock and Dam on the Mississippi River. Last week, I had an appointment with the director of that facility, and the appointment was cancelled at the last minute. Looking around, I thought it looked at least interesting, so grabbed my camera and started walking around on the sidewalks. It should be noted too that there was nothing indicating this was a "restricted area." To the contrary, I was actually in the parking lot of the public visitors center and museum. I had simply driven back to the area via widely open gates marked "Research facility and museum." The sidewalks I was on were the ones leading up to the entrance to the museum. In any case, as I was walking back to my car, someone in a uniform(but in a fairly ordinary unmarked car) drove up and asked me what I was doing. I explained, and was asked a half dozen different ways what I was photographing, why I was there, what I was doing, and the like. I kept asking if there was a problem or if I shouldn't be doing what I was doing, and was just met with the same questions. I even asked if he'd like to look at what I'd taken(which I know I don't HAVE to do, but thought it might end the encounter) but everything I asked or answered was just met with either another question along those same lines or "I was just checking to make sure you were alright/everything was alright." The guy's parting words were "just wanted to make sure you were alright." Nothing became of it-I wasn't asked for ID or anything along those lines, but I couldn't help but feel that I was under a microscope or feel like I was doing something wrong for even being there. Looking around the web a bit, I found pages where the COE seems to have contests for other lock and dam photos, so it seems that for at least some of their facilities, photography is actively encouraged. Does anyone have any experience or advice in this regard? And by the way, no I don't think that hassle produced any photographs worthy of note, but I think the site warrants a revisit when it's not so dreary(or at a better time of day) provided I don't feel like a criminal doing it.