Hoover Dam is enormous. Much bigger than you'll ever imagine until you see it. I'm normally not interested in engineering, but our tour and walk around Hoover Dam was really interesting (and it was great to take a break from Vegas. It's only about 30 miles from the Strip).
Of course, the highlight of the "tour" is being able to walk along the Dam itself. It is very powerful to see. It was also fun to walk from one time zone to another, as you crossed from Nevada into Arizona.
I recommend spending 1/2 a day at Hoover Dam as this is truly a man-made wonder. We were not disappointed. Its' definitely worth a visit.
