When we first saw the exterior of this Rolling Hills, California mansion, we thought it was just another big estate to envy. We had no idea what was hiding behind, or rather underneath, those front doors.

Owner John Z. Blazevich created the 50,000-square-foot palace called "Hacienda de la Paz," with five underground floors of wonder, after finding out that homes in his community could only be single-story. According to the Los Angeles Times, this place has secret passageways, a Moroccan-style bath and a tennis court (did we mention this is all underground?) That's in addition to jaw-dropping views from the outdoor pool, ceilings that rely on nothing but gravity to stay put and eight acres of trees.

It's being listed by Hilton & Hyland/Christie's International Real Estate for $53 million if you're interested. And while that number might take a few seconds to process, the listing agent, Marcie Hartley, told the Los Angeles Times it's worth every penny. "While 'one of kind' may be a tired and overused real estate cliche, in this case it is simply the absolute truth."

Scroll through our slideshow to see photos of the amazing manse, and head over to the Los Angeles Times for more information.

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  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

  • Credit: <a href="http://www.marksinger.com" target="_blank">Mark Singer Photography</a>

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