Holy Hindu shrine in an enormous, monkey-filled limestone cavern.

A licentious look into Singapore's past, full of disorderly bric-a-brac and disreputable characters.

A manifestation of modernist architectural ideas, this massive, multi-purpose building was one of the first of its kind in Southeast Asia.

This fountain was once heralded as the largest in the world.

This statue once earned the distinction as one of the "Three Major Disappointments of the World."

The most playful of the life-sized statues that make up Singapore's "People of the River."

The busy transport hub is home to the tallest airport slide in the world.

Singapore's landscaping project is home to 18 incredible Supertrees.

A musical instrument played by the sea.

With over 10,000 lights, this engineering marvel lights up the city after dark.

This extraordinary, multi-pillared monument depicts the fascinating history of Georgia.

The largest Roman amphitheater in the Balkans once held over 20,000 people, but managed to lay hidden for hundreds of years.

A memorial museum to the political prisoners who were held at Sighet Prison, once one of the most feared places in Romania.

A medieval church built up to defend its village.

A celebration of all things tacky, garish, and bizarrely creative in the Romanian capital.

Once an opulent Art Nouveau hotspot, the Constanța Casino is one of Romania's most beautiful abandoned buildings.

This once-derelict building is now one of the most beautiful bookstores in the world.

This elaborately decorated, fairytale-like Romanian royal palace is one of the most striking castles in Europe.

A small town Romanian cemetery filled with darkly humorous gravestones.

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

A massive collection of petroglyphs dating back some 40,000 years.

A unique museum dedicated to culture and artistry of carpet weaving.

This mysterious but iconic tapered tower appears in many Azeri fairytales and legends.

The building's fluid, wavelike walls are a true feat of architectural ingenuity.