For anyone there for a few days, it's worthwhile renting a car, as there's plenty to see within 4 or 5 hours.
Speed a little and you can get to the Grand Canyon, South Rim, in 4 or 5 hours. Well worth the drive.
Death Valley is within striking range, about 3 hours away.
Valley of Fire is worth seeing, and as I recall, it's an hour or two northeast.
Hoover Dam is about 30 minutes outside the city.
Laughlin is about 1.5 hours south.
Slightly below Laughlin is Lake Havasu, one of the most decadent spots I've ever been to
. Hit that place on a long weekend - you won't be disappointed.