The city-sized home palace of one of ancient Egypt's most powerful rulers gives us a rare look into the lives of the epoch's rulers.

This ancient structure is widely thought to be the oldest intact pyramid in the world.

Possibly the oldest church in Barcelona, this basilica has its pagan and Christian mythologies all mixed up.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

A rare set of strings by famed instrument maker Antonio Stradivarius is on display in the Royal Palace.

Over two centuries old and counting, Madrid's massive botanical garden contains one of Europe's only desert environments.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

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

Padlocks cover this rickety footbridge with love.

The haunting complex honors the millions of Ukrainians who died in the forced famine under Soviet rule.

The deepest metro station in the world.

When you've got to go, you've got to go.

A reconstructed medieval gateway that was the magnificent entrance to the capital city dating back to 1037.

This unassuming museum's slogan translates to “there is a limit of sadness, anxiety has no limits."

The largest catacomb system in the world.

The gloomy ruins that inspired Bram Stoker to bring Dracula to life.

An unusual round church in London with a Templar past.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

Famously misunderstood wonder of the ancient world

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.