The shopping malls are the elephants of commercial architecture, massive structures which combine retail stores, food outlets, and entertainment under a single roof. The largest in area (though not in retail space, since much of the mall is devoted to entertainment and public space) and perhaps most extravagant is the Dubai Mall in the United Arab Emirates, designed by DP Architects of Singapore and opened in (2008), which features, in addition to shops and restaurants, a gigantic walk-through aquarium and underwater zoo, plus a huge ice skating rink, and, just outside, the highest fountain and tallest building in the world.