Among the high rises of Tempe, there's a mountain with an A on it. It's also known as Tempe Butte or Hayden Butte, but the 58 foot A gives it its local name.
The A has been put there by the Arizona State University and it is very dear to the student population. During athletic rivalries, the A has been painted by other schools. To protect it, students will stay up all night guarding it.
If you've not come to paint anything, it's also a nice place to go for a view from above.