Hike to Mt. Diablo summits (from North side)

Why should the pro racers be the only ones to get a great workout today?
Hike to the summits of Mt. Diablo from Clayton. Top out on the North Summit then traverse over and top out on the South Summit in time to see the (hopefully) dramatic finish of the penultimate stage (7) of the Amgen Tour of California.
~4000ft elevation gain
Bring lunch and other picnic goodies as we should get to the South Summit, aka finish line, early and will likely chill there for a few hours until the racers catch up with us.
Hike details:
http://www.everytrail.com/guide/north-peak-at-mount-diablo-state-park
Amgen Stage 7 details:
http://www.amgentourofcalifornia.com/Route/stages/stage7.html