Planning Your Time
Three to five days is an optimal amount of time to spend in Phoenix if you want to relax, get outside to hike or golf, and see the main sites like the Heard Museum and Scottsdale. Extra time will allow you to make some interesting side trips to nearby places like Arcosanti, Wickenburg, Cave Creek, and Carefree.
Remember that the Valley of the Sun is sprawling, so planning ahead will help you save time and gas. If you're heading to the Heard Museum downtown, for instance, you might want to visit the nearby Arizona Science Center and/or the Phoenix Art Museum, too, both of which are close to the light-rail line. If you're going to Taliesin West, do so before or after spending time in Scottsdale.
If you're driving to the Grand Canyon from Phoenix, allow at least two full days, with a minimum drive time of four hours each way. You can always anticipate slow-moving traffic on Interstate 17, but in the afternoon and evening on Friday and Sunday, lengthy standstills are almost guaranteed, so plan ahead if you have a flight to catch.