Major tourist destination known for its bubbling mud-pools and hot thermal springs.

This strange geological landscape erupts with sudden bursts of water.

The glacier tucked within a New Zealand rainforest.

Dolphins, ancient clams and hundreds of waterfalls make this one of the world's top tourist destinations.

Tubing through a cave lit with glowworms is a magical underground experience.

If a glacial river suddenly diving into a sheer chasm via a dramatic, multi-stage waterfall isn't peak Iceland, it's certainly close.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

Danish tourist destination well known for open stalls where vendors sell marijuana on the street.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

Copenhagen's celebrated theme park and gardens.

A maze of crosses marks the jumbled divide between the Netherlands and Belgium.

This neon blue river gets its color from a unique mix of bacteria and volcano minerals.

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

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

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

An architectural oddity hides in plain sight on this iconic London bridge.

You will not be able to miss this building.

Graffiti from the 16th and 17th centuries cover the walls of this part of the Tower of London.

The commemorative stone column conceals a secret laboratory.

The ritual has been performed uninterrupted for nearly 700 years.

Originally built for London’s cab drivers, this bright green hut now serves anyone a hot drink or meal.

The "lost friend” is the most famous of the six moai statues that were removed from Easter Island.

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.