A hotel in China offers guests a spectacular and unique view, as they swim in a pool with a glass floor while dangling 24 stories above the busy Shanghai streets.

The Holiday Inn Shanghai Pudong Kangqiao's swimming pool is what's known as a cantilever pool, in which part of the pool extends beyond the ledges of the building. The cantilever engineering allows the pool to extend over the edge of the hotel's wall while being anchored only at one end. The engineering concept has been used on numerous objects, from bridges to farmhouses. Even the airplane on the bottom right of the image above uses cantilever engineering. But you don't see very many examples of this structural design being applied to swimming pools. Particularly not ones with a glass bottom way above a busy metropolitan street.

CNN reports that the extended bridge gives swimmers the sense that they are traveling through the air, all while pedestrians can view them from below.

"We wanted to provide our guests a unique swimming experience, and let them feel they're vacationing even in a bustling city," a spokesperson for InterContinental Hotels Group, parent company of Holiday Inn, told CNN.

Holiday Inn says it sought input from a number of professional designers and even aerospace experts before beginning construction.

You can view a photo of the pool—which is about 98 feet long, 20 feet wide and 5 feet deep—from inside the hotel.

To use the pool, you have to be a guest of the hotel or a member of its gym. But if you happen to be in the area, rooms at the hotel start at $125 per night, compared with the $2,400 annual gym membership.

There are other cantilever pools around the world, though most are located in residential properties and not so high up in the air. This is the first such pool built for commercial purposes in China, and was designed by the Singaporean firm Chan Sau Yan Associates.

The Atlantic has a gallery of other gravity-defying pools.