It may be surprising to find out there are real waterfalls in Arizona, but the Grand Falls of the Little Colorado River are actually some of the biggest falls in the United States. The Grand Falls are taller than Niagara Falls at 185 feet, but the water is generally very muddy and almost looks like chocolate running over cliffs during certain times of the year.
Located a short drive from Flagstaff, Grand Falls is 30 miles northeast of the city on the Navajo Indian Reservation. Take your family out for a picnic overlooking the falls, as admission to the area is free, but stay out of the riverbed because it may not safe to walk through when the current is strong.
The best times to see the Grand Falls are March through May when there is more water flowing from winter snowfall in the White Mountains or spring rain. Several months of the year and times when there have been very little precipitation leave the falls to nothing more than a drip, if there is any flow at all. These falls aren't the easiest to find, but any concierge at the hotels in Flagstaff should be able to give you directions, and they are definitely worth the trip!