Thanks to my addiction to good food (and I mean the food that tastes good, not good for you) my doctor and cholesterol levels insist that I get more exercise. Not a gym bunny, I look to hiking/walking as my exercise of choice. Thunderbird park is just the right place for me. So quick and easy, in and out. The steepest hill and loop around back to the parking lot generally takes me 40-50 minutes and is a lovely hike. Easy, convenient and clean. Great place for beginners or low level work out people such as myself. :)