Dolmen?

What looks like a dolmen appears from closer of to be a derelict kind of picnic table. At least part of the upper stone is flat enough to put a mug of coffee.
However, the stones to sit on are so small that I would not be able to stand up again without aching knees. The table itself is also 50cm or less high.
Well, perhaps it was for kids? But then again, the nearest school is a bit far away. Or better: was far away, because of course nowadays no schools in 100 inhabitant-villages exist.

Thanks to Marlieske for hosting the Derelict Sunday challenge.