'Mystery' home, Pensmore Mansion, under construction in the Ozarks

A “mystery” mansion being constructed in the Ozarks is getting a lot of attention on the Internet Thursday.

Pensmore Mansion will be one of the largest homes in the country when it is completed in 2013, according to and article on Forbes.com.

The Missouri home, estimated to be 72,000 square feet, beats Aaron Spelling’s former 56,000-square-foot California home, which was recently purchased by billionaire heiress Petra Ecclestone.

The article says Pensmore sits on more than 500 acres and will boast 13 bedrooms and 14 baths.

According to an article in The New York Times , many have insisted the giant concrete structure is actually a military bunker. While others have speculated it is a secret facility designed to house extraterrestrial visitors or possibly a low-profile getaway for Brad Pitt and Angelina Jolie.

The giant home will reportedly be earthquake and tornado resistant.

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