I saw this picture before my hike to top of Mt. Diablo yesterday. I did not see this official summit anywhere, but I think the reason was that it is located in the visitor's center, which was closed due to power outage. I ended up going into the rotunda, which is just a bit higher.
"Got tight last night on absinthe and did knife tricks. Great success shooting the knife into the piano. The woodworms are so bad and eat hell out of all furniture that you can always claim the woodworms did it."