This riddle sounds like it should be about an animal or something racing in circles:
What can run around a backyard without ever moving?
The answer is a fence.
A fence can run all the way around the edge of a backyard, but it stays fixed in place. The trick is the word “run.” We usually think of running as movement, but the word can also mean extending along a particular path or boundary.
That double meaning is what makes the riddle work. Once you stop picturing something with legs and start thinking about what surrounds a yard, the answer becomes much easier.
Answer: A fence.
It is a simple wordplay puzzle, but the wording is just misleading enough to make many people overthink it.
