My girlfriend and I were hiking in Sequoia NP, and as we were walking around a slow left turn and looking at the view on the right we walked right up on a bear. We were less than ten feet from it when we saw it which wasn't the scary part. The scary part was once it saw us it turned and trundled a few feet farther away and then stopped, turned and stared us down for a second. After a minute it turned a walked away, which was quite a relief. But maybe I was more startled than scared, he didn't seem too aggressive.
...To wander on in a huge forest without thought of return...