Its a little hard to get to...but well worth the effort. The Rock Factory is a really cool place overlooking Lake Powell. Its right off HWY 89 on the way out of Page AZ headed to Kanab.
Not far from Page and best shot in the morning or even better in the evening with clouds in the sky. Some say that a thundery atmosphere in the late afternoon is just excellent for taking photos.
Tips for morning / afternoon shots: The rim blocks the best light until about an hour after sunrise. At sunset the rim also blocks the best light but not as much as after sunrise.
Best months are from April to August with a huge variety of amazing blooming flowers. However, worth a visit any season. Can be crowded on weekends during the summer. If you visit in summer, you definitely shouldn't miss the Rose and Light Festival (Rosen und Lichterfest): For one weekend in June thousands of lights illuminate the garden!