World's largest building in China equivalent to size of 329 football fields

The city of Chengdu in China unveiled what is said to be the world's largest free-standing building this week.

The 18-storey New Century Global Center may not be very tall, but it boasts 1.2 million square feet of floor space.

In fact, the new structure so big that it could house three US Pentagons, four Vatican Cities, or 20 Sydney Opera Houses, according to the New York Daily News.

Retail shopping is the primary purpose of the massive building.

Inside the cavernous space, there is an indoor beach and massive wave pool that will be illuminated 24 hours a day by an artificial sun and bordered by a horizon projected on a 164-yard-long LED screen.

Even the gentle breeze you'll feel while riding the waterslides at the Paradise Island water park, which accommodates 6,000 visitors, is manufactured.

If water isn't your thing, you could try ice skating at the regulation-size rink, or you could catch a film on one of the building's 14 IMAX screens.

Those who need a nap can check into one of two five-star hotels on the property, each offering 1,000 rooms.

The main activity at what officials hope will become one of the world's leading tourist destinations is shopping.

Retail space will comprise the bulk of the building's 420 acres of floor space, roughly the equivalent of 329 football fields.

Across a courtyard, British-Iraqi architect Zaha Hadid's 500,000-square-foot Chengdu Contemporary Arts Centre features ample gallery space, as well as three performing arts theaters.