This little medieval church hidden in the center of Yerevan was lost and rediscovered—twice.

The ruins of a 13th-century monastery that long served as a place of refuge from wars and raids.

Seventy-five miles of limestone caves host more than a million bottles of wine beneath a sleepy Moldovan town.

In a 345-million-year-old cave that's 200 feet underground, dinner awaits.

The walls of these four caverns are filled with art that dates back to the earliest human presence in Europe.

Grotto replete with mystical designs laid out in glued shell mosaics.

The architect of this fanciful complex called it an "oasis for humanity and nature in a sea of rational houses."

The largest portal tomb in Europe has a capstone weighing around 150 tons.

This magnificent brick dome was made with an unusual design method.

Largest private bird collection in Iceland, formed from a tragic accident.

This fairytale-like structure is the last turf church ever constructed in Iceland.

Legends of treasure and spirits flow from this this fairy tale-like oasis.

This medieval citadel once guarded the western entrance of the Pamir Highway.

A massive wintry wall of snow up to 66 feet tall flanks a highway through Japan's mountains.

Ruins of a Carnegie family mansion on Cumberland Island.

Lumps of significant stone from around the world surround a flaming monument for peace.

These ancient sunken lanes were naturally tunneled into the soft ground by countless footsteps.

A medieval, mosaic-lined baptistry built by a heretical Christian sect.

The bizarre visions of H.R. Giger, tucked away in a Swiss medieval city.

The steepest classic funicular in the world glides along a dizzying incline.

A once-thriving hotel in the Swiss Alps couldn't compete with climate change.

A stunning hermit's shrine on a steep rocky spur in Northern Italy.

The awe-inspiring ship from the golden era of cruising has an incomparable history and a reputation as one of the world’s most haunted places.

An otherworldly, fossil-rich cobble beach holds Viking graves, cairns, and other remains.