Perhaps you should check out the Paulinskill Viaduct as well. A very impressive piece of engineering history. Here's some shots that I took there two years ago, on a blustery Feb afternoon (Note: do NOT climb the bridge in the wind, it made for some scary moments. Also, be careful of manholes w/o covers.)

On that trip, I captured what I believe would have been some of the best waterfall photos I could have possibly gotten (Waterfall streaming down massive icicles). However, its VERY hard to capture a photo when you forgot to load film back into the camera .