Toronto's downtown has 18 miles of underground pedestrian tunnels

Boston opened the first subway tunnel in the US in 1897

By the end of the 19th century, nearly 400,000 people were packed into less than a square mile of downtown Boston, with 8,000 horses pulling trolleys through streets choked with noise, manure, and congestion. This prompted the city to pursue a then-controversial subway system.

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.

How congestion pricing is trying to fix downtowns

Billions of gallons of gas are wasted each year as US drivers sit in traffic losing billions of hours of time. The congestion problems big downtowns face has led to innovative interventions to try to stop the traffic, including congestion pricing, a...

The simplicity of immersed tube tunnels

Tunnels have traditionally bored holes through the earth below the water. On the other hand, immersed tube tunnels connect hollow, massive sections in trenches along the floor of the body of water. Each section is built on land, floated to the site, submerged, and connected. This method saves money by reducing expensive underground work, and it preserves an area's aesthetic appearance.

NYC's first subway was built largely in secret

In 1870, Alfred Ely Beach secretly tunneled under Broadway in 58 nights, disguising his pneumatic subway as a mail tube to fool Tammany Hall, the corrupt political machine that ran New York City. Nearly half a million New Yorkers rode it before politics, and a stock market crash killed the project.

NYC congestion pricing a year in: traffic is down, transit is up

Manhattan's congestion pricing program has quietly become a success story. WNYC reporter Stephen Nessen examines why the original backlash to the concept has faded, how New Yorkers adjusted, and what the city's experience shares with similar policies in Stockholm and London.

The archaeological sites uncovered through London's Crossrail Project

The Crossrail Project is an underground train system in London, which saw 26 miles of new tunnels created over more than a decade. The project provided unique access to long-buried layers of London's history, and a massive parallel archaeological excavation took place.

The 15-minute city lets residents meet their daily needs within 15 minutes on foot

Many cities have been designed with inefficient layouts that waste time and lower the quality of life of those who live there. In the 15-minute city, essential services—including work, food, education, and health—should all be located within a short walk or bike ride from where people live.

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.

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.

How the underground maze below the Gaza Strip works

Hamas militants have constructed a web underneath the Gaza Strip filled with tunnels, residential areas, bunkers, and more. This article and illustrations explore the underground maze as detailed in photo and video evidence and witness accounts.

Abandoned malls prompt 'liminal' vibes of being stuck in time

A Toronto-area tour of empty malls brings participants face-to-face with the past. Part nostalgia, part archaeology, this meditation on the "liminal" spaces of a bygone era provokes eerie reflections on our relationship to time and place.

45% of Americans have no access to public transit

Most US transit was built on a monocentric design, funneling riders into a downtown center. But today's most common commute is from suburb to suburb, meaning the system is built for a work pattern that no longer exists.

One graffiti artist turned a train tunnel into his gallery

Chris Pape, also known as Freedom, began exploring a tunnel under Manhattan's Riverside Park when he was a kid. As he grew more involved with graffiti, he turned its walls into a massive art project, one that reflected both the history of graffiti and the people who made the tunnel their home.

Washington DC's streetcar network built the modern American suburb

Washington's first electric streetcar line launched in 1888, and real estate developers quickly built lines to open new neighborhoods. A 35-minute ride from Chevy Chase, Maryland, to downtown Washington transformed farmland into a suburb.

Connected technology improves infrastructure efficiency in smart cities

Through information and communication technologies, smart cities can provide enhanced public services and improved quality of life by managing traffic and dynamic safety policies. They can also promote sustainability by automating energy use and redirecting resources according to need.

Dubai and Barcelona are examples of smart cities

By integrating technology into public transit, utilities, and other municipal systems, these cities aim to reduce costs and enhance the quality of life for their residents. Some of these technologies include adaptive lighting, parking sensors, and underground waste systems.

Visualizing New York City's public transportation commutes

New York City is one of the largest cities in the world, and transports one of the largest numbers of commuters on a daily basis. This data visualization tells the stories of those commuters, showing the varying volume of travelers throughout the week and day, where they are going, and maps of high-traffic areas like stadiums and midtown. Dive into the data here.

Self-driving cars may upend transit before cities can build it

Austin approved a $7.1B light-rail in 2020, but components of the plan have already been cut. Simultaneously, Waymo launched a 200-car autonomous fleet across the city. Cities now face a choice: invest in decadeslong fixed infrastructure projects or embrace flexible, on-demand autonomous vehicles that can navigate anywhere.

The aqueducts and cisterns of Constantinople

The system of aqueducts that supplied Byzantine Constantinople with water had more than 500 kilometers of channels. These channels fed hundreds of cisterns. The largest were open pools (one, now drained, houses an entire modern shopping center); but the most impressive were vast covered chambers like the Basilica Cistern, still a highlight of any visit to Istanbul.

Read a complete history of urban mass transit in the United States

Explore the rise and fall of American mass transit, from the horse-drawn omnibus era through the streetcar age to the automobile's dominance. In the 1920s, streetcars carried 12 to 13 billion riders per year. By 1963, that number had shrunken to 300,000.

Niagara Falls was a key Underground Railroad crossing point

In the mid-1800s, the Suspension Bridge near Niagara Falls connected the US to Canada and served as a frequent crossing location for people escaping slavery via the Underground Railroad.

The Canadian side of Niagara Falls has many tourist attractions

The Canadian side features Ripley's Believe it or Not, Louis Tussaud's Waxworks, tunnels behind the Falls and more. A short walk from the falls leads to Clifton Hill, packed with arcades, mini golf, haunted houses, and carnival-style attractions.

Why are ancient ruins underground?

When cities fall into disrepair, it's often easier to flatten what you can and build on top. This is why modern archaeologists frequently discover ruins underground, revealing generational layers of cities rebuilt over time. This video explores major examples of this principle, from ancient Troy to even modern Seattle.

The Boring Company was created by Elon Musk in 2017

While it started out as a subsidiary of SpaceX, the Boring Company became an independent entity in 2018. Musk started it with the aim of helping reduce city traffic via underground tunnels.

How parking infrastructure reveals a region's values

As cars became more popular, the need for city parking increased. In Europe, well-established cities with limited space generally opted for more expensive underground parking beneath public spaces to preserve aesthetics. Available land and decentralized planning in the US saw more parking lots and garages built. These decisions reveal broader policy realities for these regions.

Explore metrics on the Tor network, the infrastructure of the dark web

While internet traffic within the network is concealed, public, nonsensitive data can be used to estimate the number of active users, the number of relay servers, network performance speed and reliability, etc. Researchers can use this data to indirectly identify political upheavals or censorship campaigns worldwide, such as the Arab Spring.

LA used to have one of the best mass transit systems in the country

A century ago, Los Angeles had one of the greatest urban transit networks in America. Today, driving in LA traffic can still be faster than taking the train. The city's rail design, which funnels traffic through a single point, fails to support a city with such a spread-out population.

The underground cities of the Byzantine Empire

This TED-Ed video explores the mysterious cave cities of Cappadocia. Although their oldest sections may go back to the Bronze Age, most of these subterranean complexes were excavated during the Byzantine period, when the locals went underground to take shelter from Arab raiders. Monasteries were also cut into pinnacles of the local tufa, and decorated with frescoes that have often survived to the present.

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.

The wild, early history of the tunnel across the English Channel

Britain and France today are connected by the Chunnel—a tunnel bored roughly 120 feet under the seabed of the notoriously choppy English Channel, which opened in 1994. The dream of integrating Britain with the rest of the continent this way began much earlier, with daring, physically impossible plans proposed as early as the 19th century. Check out the earliest plans here.

While constructing the tunnel connecting the UK and France, satellite positioning systems were supplemented by paleontologists on either side of the tunnel, who analyzed fossils to ensure excavation was at the correct depth.

The New York MTA is North America's largest transit system

The MTA's FY2026 budget is $21.3B, and the system carried 1.6 billion riders on buses and subways in 2024, making it by far the largest transit network in the country.

Inside the most crowded place on Earth

Once the densest place on Earth, Kowloon Walled City was a chaotic labyrinth of stacked homes, hidden corridors, and thriving underground life.

Tokyo's transparent toilets use smart, automatic glass to make cleanliness visible

Dubbed the Tokyo Toilet project, this initiative installs restrooms whose walls are transparent when empty, so users can see whether they are clean and safe. When they lock, they turn opaque for privacy. Beyond addressing two key anxieties (hygiene and security), the project lends a distinct architectural prestige to typically banal (and reviled) toilets.

A 2020 study suggests just 6.7% of Tor network users visit sites on the dark web

It did not distinguish between visits to malicious sites and traffic to legitimate institutions with .onion domains, such as the BBC or Buzzfeed, and thus claimed that 6.7% of anonymized users engage in nefarious activity. The low percentage still highlights that most users of the technology underlying the dark web do not use it to browse the hidden portion of the internet.

Transit is funded through a three-tier system, and the federal government is the smallest piece

In 2019, the federal government covered about one-sixth of the $79B spent on public transit. States and localities make up the rest. About 85% of all transit trips are taken by bus or heavy rail, and nearly 4 in 10 US transit trips occur in the New York City metro area.

Travel the 363-mile Erie Canal, the waterway that cut freight costs by 90% and opened the American frontier.

The Federal Transit Administration distributes roughly $20B annually to support local transportation

Created by the Urban Mass Transportation Act in 1964, the FTA funds and oversees the roughly 2,200 transit systems that receive federal support across the US, covering everything from subway capital investment to rural bus service.

The origin of shortest-path algorithms and how they became optimized for navigation apps

In 1956, Dutch programmer Edsger Dijkstra spent about 20 minutes developing an algorithm to demonstrate how computers could quickly determine the shortest route between Rotterdam and Groningen. Since then, modified versions of Dijkstra's formulation comprise the processing backbone of systems such as Google Maps and Apple Maps.

Why Amsterdam looks so unique

The Netherlands' capital consists of concentric canals lined with towering, unusually thin row homes, an altogether unique profile in Europe and the world. When it was growing, the city was a key trade hub, and merchants wanted direct access to waterways. Canals were built like roads, and houses were required to be very thin to allow for more homes to line the canals.

Paris and Boston were redesigned partly to combat cholera's spread

Georges-Eugène "Baron" Haussmann, who oversaw Paris's redesign in the 1800s, replaced many of the city's narrow streets with wide boulevards. This was done at least in part to bring more air and light into the city to help control cholera. Architect Arthur Gilman redeveloped Boston's Back Bay to similarly combat cholera, among other reasons.

The federal government pumped $70 billion into transit amidst reduced ridership during the COVID pandemic

When ridership collapsed by 75% in the spring of 2020, Congress sent transit agencies nearly $70B to help them survive. But that money has largely run out, and ridership remains 14-28% below prepandemic levels, leaving many transit systems with large budget deficits.

Who cleans the London Underground at night?

The London Underground, also known as the Tube, services millions of people every day. After the transit system closes each evening, a crew of workers known as “fluffers” gather to clean the underground tunnels. This article sheds light on these unnoticed cleaners, covering the difficulties of their jobs and the bizarre things they’ve encountered, from ghosts to nesting pigeons.

Niagara power helped electrify early New York City

Tesla's AC system at Niagara Falls was so successful that electricity generated there lit up Broadway theaters and powered NYC's subway system in the early 1900s.

Microforests in urban environments may help combat climate change

Areas of densely packed native trees and drought-tolerant plants within cities can pull carbon dioxide from the air, cool surrounding neighborhoods, and support local wildlife. The idea behind microforests traces back over 50 years to Japanese ecologist Dr. Akira Miyawaki, who promoted planting whole ecosystems to restore degraded land.

Disney World's Magic Kingdom includes utilidors—an underground system of tunnels and passageways—to hide the park's maintenance operations.

The National Mall once had canals and rail lines

In the 1800s, the National Mall looked nothing like it does today. Canals, rail lines, markets, and industrial uses crisscrossed the Mall before later redesigns cleared it into a unified civic landscape.

Many issues facing urban environments cannot be solved by smart technologies

Although connecting systems to the Internet of Things can provide improved efficiency in municipal systems, problems such as limited affordable housing are driven by larger socioeconomic factors. Some experts suggest that local governments should focus resources on practical solutions to these issues rather than investing in smart technologies.

Woven City at the base of Mount Fuji in Japan

The Woven City at the base of Mount Fuji in Japan is a ‘living laboratory’ for new technologies. It is being developed by Toyota subsidiary, Woven Planet, and will be the world’s first programmable city.