I like to go on hikes with outdoors-oriented Meetup groups. I like hiking anyway, and I frequently find someone to have an interesting conversation with. If I don't, no problem, it's still fun to do the hike anyway even if I don't talk to anyone.
To expand on this a bit, I also find these Meetup hikes great for learning about trails in my area I otherwise probably wouldn't know about, so I can go back to them on my own later or with a friend or date. Also there's a lot of singles in some of these hiking groups so it can be a good way of finding new dates.