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

A striking symbol of the Bulgarian capital.

A marvel of Byzantine engineering under the streets of Istanbul.

On any given day this sprawling market houses literally tons of government-regulated gold, gems, and precious metals.

A preposterously luxurious hotel with gold-plated iPads, Rolls Royce chauffeurs, and a staff that trains by watching "Downton Abbey."

This trio of Australian rock spires may have inspired aboriginal legend or just modern tourism.

Cockatoo Island is a Heritage-listed island in the middle of Sydney Harbour.

A self-funded cemetery with a long list of inhabitants.

The glacier tucked within a New Zealand rainforest.

A glacier pocked with ice caves and surrounded by rainforests.

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

The world's only complete colossal squid specimen is on display at the Te Papa Museum.

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

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

This sheep farm has been forever transformed since being built for “The Hobbit” film series.

Handcrafted thermal spa washes away each night with the tide.

The platform atop this verdant volcano was built with the help of a royal elephant.

A New Zealand communications tower stands as the tallest structure in the Southern Hemisphere.

This cavernous swimming spot doubles as a home to the largest known colony of bats in Central Asia.