A perfectly circular lake is formed by the crater of an ancient underwater volcano.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Macabre astrological automaton clock dating to the late 1400s.

Beautiful Austrian natural history museum with carved ceilings and row after row of ancient taxidermy.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

The beautiful baroque library of the Hapsburg empire.

A neolithic tomb converted into a tiny chapel.

The "Little Ones," show Portugal in full miniature splendor.

One of the largest Roman settlements in Portugal.

"Portugal's Stonehenge" is made up of nut-like stones aligned with the heavens.

This crumbling Portuguese ruin overlooks the populace it once ruled.