Why are ancient ruins underground?

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

The ancient engineers inspiring modern building practices

Modern concrete structures need replacing every 50 to 100 years, so why are buildings by the Maya, ancient Rome, and ancient China still standing strong? This article details how scientists are looking into humanity's past for clues on how to craft long-lasting structures. Part of the problem is adopting old material recipes to hold up to modern demands.

Why is there an archaeologist in my trash can?

Archaeologists have always been interested in rubbish—sites such as waste heaps, middens, and latrines can be some of the richest places to learn about the human past. But the type of rubbish we're leaving behind is changing, and much of it now...

Urban planning in ancient Rome

Ancient Rome represents one of the earliest examples of coordinated urban planning from a central government for which researchers have access to contemporary records. This review from MIT showcases ancient Roman cities built on various types of grids, from rectangular outlines to those shaped around two intersecting axes, with several examples and maps provided for each.

Machu Picchu, 101

Machu Picchu was built right on top of two intersecting fault lines, which makes it even more baffling how its temples and terraces have survived for more than 500 years—especially since no mortar was used to hold the precisely cut stones together. As this three-minute NatGeo video explains, this ingenious construction method allows the stones to bounce in place when earthquakes hit, shaking and rattling but rarely collapsing.

Essential pipes, sewers, and cables lie buried beneath New York City

The Department of Design and Construction offers a tour of its work sites, explaining the complex systems that exist underground. Gas, electrical, telecom pipes, and many others, sprawl out underneath the entire city, with dozens of maps that help workers know where they're placed. This layout is unusual compared to the rest of the country, where wires are often present and visible above ground.

Explore the archaeological treasures of Pompeii, the city buried under volcanic ash when Mount Vesuvius erupted in 79 CE.

The art and architecture of the devastated Pompeii

Long buried under feet of ash, the city of Pompeii's discovery millennia later sparked a world of imagination and tragedy. See a collection of paintings, buildings, and photographs from the city all in one easy-to-browse gallery.

See ten of the most amazing Mayan ruins

Hidden beneath the jungles of Mexico’s Yucatán Peninsula, Maya temples, pyramids, and cities reveal the civilization’s vast construction ambitions. Decades of archaeology have uncovered these sites, which are explored in detail in this guided video tour of 10 significant ruins.

A history of China's ancient hidden tombs

Like many ancient cultures, the Chinese had a tradition of burying the dead in elaborate tombs, which would serve as both burial places and residences for the deceased. Archaeological evidence of these tombs, including those of former emperors, provides insights into the country's cultural evolution.

Smart cities have been more successful when upgrading existing infrastructure

Building urban landscapes with smart technologies from scratch has sometimes produced futuristic-looking yet sterile environments that struggle to attract residents and justify high costs. Enhancing existing areas while retaining their historical and cultural touchstones has proven more appealing in many cities.

Video games are helping to preserve cultural heritage sites, further archaeological study

When Carmen Sandiego swept onto the video game scene in 1985, the deluxe version of the game included historic photographs from National Geographic and music from the Smithsonian. Read this article to learn about the overlap between gaming and ancient architecture.

Fossils form in environments where dead organisms can be rapidly buried

Such landscapes enable corpses to be encased by terrain before significant decay occurs. They are most commonly found in river deltas and sinking coastal regions, where sediments accumulate over time until geological forces expose the areas to erosion, revealing embedded fossils.

Modern landfills use layered liners, leachate systems, and gas monitors to safely contain waste

Today, landfill engineering is far more complex than a hole in the ground, which was largely the system cities used less than a century ago. This video explains how it actually works.

Reconstructing an average day in ancient Egypt

Egyptologists can reconstruct the intimate details of everyday life in the ancient civilization by studying the archaeological material preserved in tombs, monuments, and partially intact neighborhood layouts. Watch a comprehensive tour of the daily habits and lifestyles of ancient Egyptians with expert Dr. Joann Fletcher.

Graffiti dates back to at least ancient Pompeii, where citizens scrawled messages to one another on public walls

Teotihuacán was already ancient when the Aztecs encountered it

By the time the Mexica reached Teotihuacán, the vast city had been abandoned for centuries. First settled around 400 BCE, the inhabitants developed monumental temples, canals, and a carefully planned urban grid centered on the Avenue of the Dead.

Human settlements may be older than previously thought

This narrative article follows an archaeological team as they sift through the remains of Nahal Ein Gev II, an ancient village near the Sea of Galilee in Israel. Abandoned about 12,000 years ago, the site has been investigated for years and...

Disney World's Magic Kingdom includes an underground utilidor

Walt Disney viewed everything happening in his parks as a performance and didn't like it when that performance was disrupted by necessary aspects of the park's maintenance, like trash collection. With Florida's Disney World, the company corrected that problem by building a massive area underneath the park to be used as a "backstage."

The unbuilt monuments of Washington, DC

The capital city of the United States famously was built in a swampy area, with dozens of memorials, monuments, and more spanning its vast and complex design. This video explores five monuments that were either built or were rejected as alternatives in the sprawling District of Columbia on the banks of the Potomac River.

Atlantis and the apocalypse: the world of fringe archaeology

A Netflix series called "Ancient Apocalypse" claims that a thriving civilization was wiped out during the ice age by comets and floods, but left humanity with science and technology. Experts call this “pseudo-archaeology.” This hour-long podcast...

Why are subway walls tiled?

In the early days of subway tunnels, architects needed to deal with dirt and moisture and make the cavernous stations less dank and dark. Ceramic tiles were easy to clean, and their glossy, bright finish helped illuminate the cave-like areas.

Lidar's discoveries: 32 forts revealed by the laser tech

Lidar is a cutting-edge tool using lasers from an aircraft to map the elevations of huge swaths of land across the world. This technology has been especially effective in archaeology. It has revealed dozens of lost major historical sites concealed beneath overgrown brush and forests. From Canadian forts to Mayan settlements, check out these 32 significant finds from lidar.

See a 3D reconstruction of Tenochtitlan, the Aztec capital that was home to an estimated population of 200,000 to 400,000.

How search and rescue teams remove survivors from rubble

At any time, large-scale seismic activity can devastate entire regions, often with little warning. Emergency responders, then, are perpetually on call. This is particularly critical in areas with poor infrastructure.

Why water towers are built that way

Inside the architecture of Pyongyang's Kim dynasty

Since the bombings during the Korean War wiped out much of Pyongyang in the 1950s, three leaders of the Kim dynasty of North Korea have remade the ancient capital from the bottom-up, designing workers monuments, vast streets, and collectivized living spaces. Take a look inside the reclusive city with this architectural analysis accompanied by photographs.

Explosive volcanic eruptions happen when magma pressure overcomes rock strength

Magma usually stays underground because of a balance between its upward pressure, the weight of the Earth’s crust above, and the crust’s rock strength. Landslides can reduce crust weight, while built-up gas pressure can strengthen magmastatic pressure.

Stanford built a Google Maps for the Roman Empire, revealing how much it cost to travel in the ancient world

Volcanoes 'die' when their supply of magma runs out, if they are shifted away from their underlying magma reservoir, or if they get clogged by collapsing or their magma cooling back into rock.

See photos of Meteora, a mountainous site in central Greece, home to 14th-century monasteries perched atop soaring outcroppings.

In 1915, workers recovered a submarine-like vessel from the Chicago River, prompting fears of German espionage

Artificial coral reefs have been 3D printed from nontoxic, biodegradable terracotta clay, which coral polyps have used as a foundation for rebuilding marine ecosystems.

Frank Lloyd Wright's houses are historically hard to sell because they're old, subject to local landmark commissions, and often unfashionable

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

Apollo astronauts left items in the moon's 'toss zone,' including golf balls, family photos, and bags of human waste, to make room for lunar rocks.

Researchers believe the brain consolidates memories, processes emotions, and plans for the future during dream states

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

Some coin denominations have ridges etched on their sides, partly to prevent counterfeiting, in a practice called 'reeding.'

Watch this video that uses Lego bricks to explain how venture capital works.

Watch how algorithms can be designed to train themselves and self-improve without human input, to the point where the optimized code is too complex for programmers to understand.

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.

See how fireworks are made and learn how metals like magnesium and copper are responsible for different colors.

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

To reduce wrinkles in clothing, research recommends gentle wash cycles with more water and tumble drying with smaller loads and longer times.

Fear or disgust related to clusters of holes and cracks, called trypophobia, may stem from evolutionary processes to help us avoid pathogens.

Long before Major League Baseball began allowing instant replay for balls and strikes, an umpire reluctantly used the technology to determine whether a hit was a home run, a move that inadvertently ushered in a new era for the sport.

The first steps to rebuilding your credit score include getting to know exactly what's on your credit report and figuring out how far you are from the '700 club,' or 'good score' range.