A scattered trail of street art adds a pop of color to the city's stark structures.

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

This bronze boar's snout has been rubbed to a golden sheen by visitors seeking good fortune.

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

Watch butterflies take flight before you fly.

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

Singapore's oldest Hindu temple.

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

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

This amazingly well-preserved villa just outside Pompeii boasts rare examples of ancient Roman paintings.

A small window on Via Piella offers a lovely and rare peek at Bologna's lost canals.

Two very green residential towers cleaning the air in one of Europe's most polluted cities.

Pompeii's less famous neighbor is still revealing her secrets.

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

Copenhagen's celebrated theme park and gardens.

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

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

A beautifully eclectic mix of architectural styles.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

An abandoned Ecuadorian prison that once held ex-presidents and notorious con artists is now a carceral museum.

Countless grotesque faces stare out from this eerie Prague art wall.

A concrete mushroom that divided Stockholm residents for nearly a century.