We like the Geocaching event at Lake Manatee state park. There is trails to walk and geocaches on the trails to locate. Then in afternoon we had hot dogs to eat for free if you bring a side dish.
At these event they place on the trails containers for us to locate, can not be in the ground, but can be in a hole in a tree or behind a tree. You have the coords for the container and you have to locate the container, sign the log sheet and replace the container for other people to find. Then that night you can go on the web site to sign in for that container and get a smiley face for all that work.
Why not find things on a trail while walking that trail and get to meet other people that likes the same t things.