Known as the “Stone House,” Casa do Penedo looks like something straight out of The Flintstones. It’s built between four giant boulders in the Fafe Mountains of northern Portugal.
Initially constructed as a rural retreat in the 1970s, the house has no electricity and is heated only by a fireplace. Its isolation and prehistoric design have made it a tourist attraction, although it’s now a private residence.
Why it’s lonely: Tucked between massive rocks on a mountain ridge, with nothing but rolling hills and sky in view.
