This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

This seemingly cursed monument is dedicated to one of Canada's great war heroes.

This impressive working clock made of 16,000 plants changes its flowers twice a year.

The third version of this tall sailing ship sits, rusted and burnt, in Lake Ontario.

Niagara Falls holds a special place in Nikola Tesla's history, so they put a statue on it.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

Soaring over the Niagara Whirlpool since 1916.

The corpse bride of Portugal.

Elaborate tile work in this railway station tells the story of Portugal.

A hidden three-foot-wide house separates these two regal churches.

A stunning 18th-century site where pilgrims ascend by a series of punishing stairs only to return via funicular.

The medieval castle built as headquarters for the Pope's secretive Knights Templar.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

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

The world's oldest bookshop still in operation.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

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

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

Replica of Seville, Spains famous Giralda, a former minaret converted into a bell tower.