A ghostly mansion in the middle of downtown Tunis.

This gaping hole in the middle of a remote mountain lake looks like a portal to another dimension.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

The luxurious circular mansion built for a Communist leader now lies abandoned.

Huge stairway leads to this massive gallery.

This small shrine is dedicated to the designer of the first Russian fighter jet and his brother, who became Chairman of the Presidium of the Supreme Soviet.

A museum dedicated to traditional Armenian clothing and their designer.

This modern tandoor eatery was once a canteen for Soviet farmers.

Called the "Armenian Stonehenge," this ring of menhirs pierced with holes may be a prehistoric astronomical observatory.

Armenia's premier center of astrophysical research was established during the Soviet era.

Nestled in a peaceful valley, this Armenian monastery may have been saved from Mongols thanks to the eyes of God.

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

The world's longest nonstop reversible cable car soars through spectacular scenery to the medieval Tatev Monastery.

Centuries before the modern seismograph, Armenian monks measured quakes with this tilting pillar.

This medieval manuscript collection has some of the most obscure and ancient texts in the world.

After visiting hours, this picturesque waterfall is essentially turned "off" to be used for hydroelectric power.

She asked for a potato cellar and over the next 23 years he gave her a network of holy caves.

A geological oddity topped with a 2,000-year-old pagan temple.

Right up until the 20th century this network of man-made caves was the biggest village in Eastern Armenia.

This Armenian monastery was carved out of cliffs and named after the spear used to stab Jesus.

The most visited pilgrimage site in Armenia once held a saint in a pit for 13 years.

A unique collection of Soviet military artifacts lies hidden away in a disused train, in the unrecognized Eastern European republic of Transnistria.

A forgotten remnant of the Soviet Union, Transnistria is an unrecognized country hidden behind a heavily militarized border between Moldova and Ukraine.