Mt Diablo was a challenge. We did underestimate  it the steep climb and the long descend. We were definitely not prepared for the challenges (specifically bugs in this hike), trying to stay covered saved the arms but nothing could safe the face. Also 680closed and way back and with traffic the return home took 2 hrs. Overall went for a long day.
So points for future Mt Diablo hiking- bug spray is a must. Return traffic can get bad and the gate for the parking only opens at 7am so it’s gonna be a long day.
But overall this is such a gorgeous hike, steep climb but the beautiful bloom all around making it worth all the effort and I spotted a snake and we even heard a few rattle snakes on the way to add to our wildlife sightings.