Advertised as a monolithic dome home, this rounded dwelling in Central Florida offers energy efficiency and weather resiliency.

This four-bedroom, three-bathroom house in Emmett, Idaho, is made from two adjoining metal silos and features views of Squaw Butte and Emmett Valley.

The crown jewel of architect Michael Reynolds’ sustainable vision, Vallecitos is a passive solar home within the Greater World Earthship Community, the world’s largest, legal off-grid subdivision.

This one-of-a-kind home was started in 1980 by contemporary artist Malcolm McCleod Brown.

Formerly rented by Jeff Bezos in the 1990s, this Bellevue abode is the true birthplace of Amazon.

Become the owner of your very own — functioning — lighthouse in the oceanside town of Yachats, Oregon.

Former Chapel on the Bay is a spiritual oasis transformed into luxury living. It’s listed for $699,000.

In Bridgeport, Connecticut, the seller transformed this one-of-a-kind, two-family home with her own artwork and renovations.

Any buyer would be “Lucky” to own this piece of pop history — Britney Spears’ childhood home has returned to the market.

This Midwest castle, built in the late 1800s, stands as an authentic reproduction of a Richardsonian Romanesque Scottish castle.

The castle is listed by Richard Bassford, leader of The Bassford Team at RE/MAX Concepts Bettendorf, for $700,000.

This other-worldly home may look like it’s about to get up and walk into the sunset — but for $2 million, it could be yours.

Situated on 17.5 acres of land that includes a private lake and beach, this one-of-a-kind property appears to have been carved right out of the earth.

On the exterior, this 11,000-square-foot estate may seem like your typical desert mansion — but step inside and you’ll see why it’s called the “Castle of Ancala.”

Vertical Horizons Tree House Paradise, which includes four tree houses fixed amongst the scenic Douglas firs, is up for sale.

This real-life Barbie dream house in Phoenix has everything a Barbie girl could want — life-size Ken not included.