They seem like standard stuff you would see in a park but you just have to give these two Dutch designers, Rogier Martens and Carmela Bogman, a lot of credit for coming up with these outdoor furniture creations.
Called the Pop/Up Installation, they were received by the Utrect, Netherlands people. The whole lot is actually a table set constructed out of heavy-duty metal. To get the three-piece furniture set out of the ground people wanting to use have to engage the pump system which is nearby.
Other than that, they can also be rearranged to different heights of the occupants choosing. Then when they are done with the furniture set, it is easily pumped back in to the ground like it was never there.