Went on a hike in San Francisco yesterday. Objectively, it was the most difficult trek I've ever done, but I had no problem with it. Most of it was uphill, sometimes so steep that I felt like I was doing lunges in the gym (got a crazy leg pump). Six years ago, which was the last period when I did frequent hikes, this would have killed me, but my endurance capacity is very solid now.
The site was an abandoned missile silo from WW2 with the purpose of defending the coast from a Japanese invasion. Didn't see any invading forces, unfortunately, and I don't think they allow visitors to fire the missiles otherwise. Would have been fun to volley some at George as a prank.