An otherwise-normal mansion is up for sale and appears to have a small town built into its basement.

The gated estate is built across four acres in Potomac, Maryland and is a rather unique offering for a buyer in the market for something both luxurious and quirky.

Potomac is a suburban community that sits about 22km north-west of Washington DC. The 7 bedroom, 8 bathroom and 3 half-bath home also features a pool house with a full kitchen.

Photo: Washington Fine Properties

Also on the property is a lighted, newly resurfaced tennis court and heated pool. Let’s not forget the grand library room either…

Photo: Washington Fine Properties
Photo: Washington Fine Properties

But venture further into the home and you’ll find the basement stairs lead into another world, complete with a cinema marquee advertising a double feature of The Exorcist and Mary Poppins, a massage parlour and pub.

Photo: Washington Fine Properties
Photo: Washington Fine Properties

The space also includes a post office, toy shop and more.

Photo: Washington Fine Properties
Photo: Washington Fine Properties
Photo: Washington Fine Properties
Photo: Washington Fine Properties
Photo: Washington Fine Properties

If this property’s for you, or if you feel like a gander at the high-end mansion decor, check out the listing through Washington Fine Properties.