There are no entrance fees at Arizona National Parks on Monday January 20th in honor of Martin Luther King Jr. Day. What a great time to visit the Grand Canyon, or perhaps Saguaro National Park. Take a hike, do some sightseeing or birding. It's all free. (Well, things like camping are not.)
Other free days in 2014 are: February 15-17 (Presidents Day weekend), April 19-20 (opening weekend of National Park Week), August 25 (the National Park Service's birthday), September 27 (National Public Lands Day) and November 11 (Veterans Day).
So now is a good time to plan a visit to one of Arizona's fascinating National Parks.