In what is now an annual tradition, the National Building Museum creates a fun, exhibit or installation in which children and adults can play. Last year it was The Beach, and the year before it was The Big Maze. This year, it is Icebergs. The museum’s great hall is filled with structures resembling icebergs, and blue mesh surrounds them to denote the water. The “water line” is about two stories high with the tops of many icebergs popping above it, like real icebergs. The exhibit is complete with an underwater bridge between two icebergs, which leads to two slides. White bean bags are scattered about, so you can sit down and relax.