A close look reveals that the Scottish monument is just slightly off-kilter.

This is Bremen’s oldest historic district, famous for its labyrinth of narrow medieval alleys lined with tiny, colorful 15th-century houses that resemble beads on a rope.

The original version of Porto's most famous sandwich is just as good here as it was a century ago.

Gustave Eiffel's masterpiece until the Eiffel Tower was built.

A site paying tribute to an 18th century Scottish fiddler

This 80-foot towering concrete structure, complete with wheel, remains a stark reminder of the coal mining that took place here between 1904 and 1966.

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

An early work of the architect Álvaro Siza Vieira, these swimming pools blend into the beach.

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

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

Ancient catacombs form the foundation for this Rococo orgy of a church.

The stunning interior of this Gothic church is covered in ornate gold details.

This restored Portuguese cafe may well be the most beautiful place in the world to grab a Big Mac.

Now famous as the "Harry Potter bridge," this impressive concrete viaduct has long been an icon in its own right.

Several plaster noses are hidden in plain sight around London's Soho neighborhood.

A church that bred legends, and served as an inspiration for the Da Vinci Code.

On this spot Lord Kelvin allegedly discovered absolute zero.

A tribute to a child prodigy who died way too young.

An 11th-century Viking gravestone in a Victorian parish church graveyard.

This tablet indicates where the tragic monarch returned to begin her tumultuous downfall.

This city square dates back to the Scottish Enlightenment and was home to some of Scotland's brightest minds.

A miniature of a lighthouse acts as a beacon for what transpires inside this location.

This monument dedicated to the legendary American showman can be found in Scotland's largest city.

A small collection of objects of a bygone era hide in plain view.