We are taking a very short(4 night) spring break vacation to Las Vegas and the Grand Canyon. We are a family of 5, three kids ages 10, 9 and 5. The main reason for being is vegas is we got cheap flights but also my husband works at a dam and loves touring different dams. So, we are definately going to Hoover dam. We already have reservations for one night in the Grand Canyon but we have one additional night to go sight seeing. I was thinking of going to Glen Canyon Dam but wondering if it is worth a trip up there or should we stick south and just tour Flagstaff and Sedona. Is there a dam around there I'm missing? Any advice?