These steeply terraced ruins are a stop along the Inca Trail to Machu Picchu.

It took 82 years and four different plaques to finally get the story right.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

This massive library holds what was once the largest book collection in the world.

France's national museum of scientific and industrial instruments.

Site of a classic 19th-century physics experiment to prove the earth is rotating.

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

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

Standing atop 2nd-century Roman ruins, this church is one of the oldest and most iconic in Old Cairo.

Ozymandias’ time-keeping temple.

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.

A perfect turquoise lake colored with glacier dust.

Home to some of the world’s darkest skies, this project blends ancient Māori culture with world-class astro tourism.

The air force base preserves its scars from the Japanese attack on Pearl Harbor.

An authentic replica of an Asian temple and garden hidden amongst the natural beauty of Hawai'i.

A trading post in the North Pole where children send letters.

Towering at a height of over 30 meters, this turn-of-the-18th-century landmark is the tallest temple in Nepal.

The former stronghold of the Malla Dynasty has remained virtually unchanged since the 17th century.

One of the largest Buddhist stupas in the world keeps an eye out in every direction.

A brick building in Kathmandu's Durbar Square is home to Nepal's most prominent living goddess.

This historic square in Nepal is home to temples dating back to the third century.

A tiny collection of traditional Japanese woodblock prints, open only when the owner feels like it.