Stuck in the middle of a modern Madrid city block are the remains of a 19th century sports complex.

Just like in Hollywood, Madrid has also a forgotten walk of fame.

The remains of a convent turned military barrack in the heart of Madrid.

An ancient Egyptian temple in the middle of Madrid, Spain.

The remains of the second-oldest zoo in Europe can be seen within these library gardens.

The only urban monument in the world designed by the great surrealist painter Salvador Dalí.

An old, deep well, connected with a miraculous, divine rescue and the patron saint of Madrid.

Famously misunderstood wonder of the ancient world

Go inside to really appreciate this 500-year-old technological masterpiece.

This palatial spiral staircase was so unusual the name "snail" was given to the noble family who built it.

This community on a small Venetian island has taken to painting their houses in bright neon hues.

A narrow ghost town built onto a peninsula behind a Colombian Slum.

The 17th-century hacienda where Simón Bolívar spent his last days before dying from tuberculosis.

A lighthouse marking the northernmost point of continental South America.

Once considered a marvel of engineering, there are now doubts about the structural integrity of this 5.4-mile cable-stayed bridge.

This unique depiction of the Virgin Mary may be the tallest kinetic art sculpture in the world.

This iconic pavilion in Barquisimeto has a roof made from 16 “petals” that open and close depending on the weather.

The world's tallest slum.

This former shopping center now acts as the eccentric lair of the Venezuelan secret police and their shadow prison.

Dr. Farid Mattar's Monument of Peace.

One of the most iconic sculptures in Caracas looks like a large orange ball suspended in the air.

Ruins of the laboratory where a mysterious doctor invented an embalming fluid and stored his mummies.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.