I recently pitched an AI-generated feature film about the world we walk over but can’t see to my colleagues at Front Seat Films.
I envisioned an epic film, like Avatar, but my colleagues rejected my idea before I could even finish my pitch.
My AI-generated movie would begin at street level, Market Street in Philadelphia at rush hour, pedestrians threading between food trucks and traffic and then the camera would descend. Through pavement and bedrock, through archaeological layers of colonial foundations and Lenape encampments, into a realm that mirrors our surface world. An intricate network of roots pulsing like arteries, some thick as subway tunnels, others fine as fiber optic cables. Mycorrhizal fungi forming living internet networks, connecting tree to tree in chemical conversation. Creatures we have never imagined, pale, eyeless, perfectly adapted, navigating labyrinths as complex as our street grid. Water moving through hidden aquifers following paths older than Philadelphia itself.
Imagine the vast ecology of it: everything connected, everything in conversation, everything serving multiple purposes. A single root anchoring a tree, transporting nutrients, housing beneficial bacteria, filtering toxins, storing carbon, communicating danger. I am fascinated by the underground because it isn’t just empty space waiting to be filled but a functioning metropolis we simply fail to see.
I believe I am on to something great, but my partners disagree. So, let me make a different pitch to my fellow citizens in Philadelphia about what our subway system is not, but could be, in real life.
The city beneath the city
Philadelphia is celebrating America’s 250th birthday this year. The city has pledged over $100 million in neighborhood investments, decorative banners, commemorative benches, seasonal planters adorning twenty commercial corridors. We have built a robust agenda for our visitors in 2026: FIFA World Cup matches, NCAA March Madness, the MLB All-Star Game, the Museum of the American Revolution’s “Declaration’s Journey” exhibition, and on and on. We hope visitors will see a city polished for its moment in the global spotlight.
But if our guests descend into our subway system, they will see infrastructure in fragile recovery from a crisis that never fully resolved.
SEPTA now averages roughly 733,000 daily weekday trips, a recovery to about 80% of pre-pandemic levels, even as the agency carries a $213 million annual structural deficit. Last summer, the crisis briefly turned draconian: in August 2025, 32 bus routes were eliminated and service was cut 20% across bus and Metro lines, with a matching cut to Regional Rail scheduled to follow. A court order and, ultimately, an emergency deal to divert $394 million from SEPTA’s capital budget into daily operations reversed the service cuts within three weeks. But the 21.5% fare increase to $2.90, tying New York’s MTA for the highest base fare in the country, stayed in place, and it stands today. So does the underlying math: the $394 million that kept the trains running was pulled directly from the money meant for accessibility upgrades, century-old station repairs, and vehicle replacement. We didn’t solve the crisis. We borrowed against the future to paper over it, and the bill on capital improvements is still due.
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Local news outlets have covered this story as a budget crisis, but it is also a failure of imagination about what underground infrastructure can be.
Underutilized network
Philadelphia’s subway system, which first opened in 1907, comprises roughly 38 miles of heavy rail across its two rapid transit lines, with dozens of additional miles of trolley and regional rail tunnel bringing the city’s total underground rail footprint closer to 60 miles. Unlike my AI-generated movie idea, where every root serves multiple functions and every space pulses with purpose, our real-life underground network remains stubbornly single-purpose: move passengers from point A to point B, nothing more.
We are squandering an opportunity to be creative. The subway tunnels maintain consistent temperatures year-round, naturally cool in summer, protected from winter cold. The stations, many built in the early 20th century with soaring ceilings and substantial footprints, occupy some of the most valuable real estate in the city. The electrical infrastructure, the ventilation systems, the structural engineering that keeps tons of earth and building from collapsing: all represent massive sunk costs, built once and maintained ever since.
Most critically, we are wasting the network effect, that exponential increase in value when infrastructure serves multiple purposes simultaneously.
What if Philadelphia’s subway system functioned more like the AI-imagined underground ecosystem, specifically designed for multiplicity rather than singularity?
Multifunctional underground
Let me propose a specific vision for Philadelphia’s subway infrastructure, drawing from innovations worldwide while addressing our city’s particular needs:
Layer One: Enhanced Mobility
The foundational use can focus on transportation, but would be radically improved. The proposed Roosevelt Boulevard Subway, that century-old dream currently estimated by PennDOT at $11 billion for its “Neighborhood Boulevard” alignment, would finally connect Northeast Philadelphia’s dense residential communities to Center City. PennDOT projects that option would draw about 62,000 daily riders, a figure transit researchers say compares favorably to recent heavy-rail projects elsewhere in the country. An earlier, more expansive 2003 study of a similar corridor projected an even larger 124,500-rider version of the line diverting some 83,000 daily car trips; whichever scale the region ultimately builds, the equity case is the same. In a city where roughly a quarter of households lack automobile access, and where half of SEPTA’s riders report household incomes below $34,000 a year, mobility is economic opportunity.
But mobility means more than trains. Copenhagen and Montreal have demonstrated that underground bicycle highways, protected from weather, separated from vehicle traffic, can transform commuting patterns. Philadelphia’s subway tunnels, many with abandoned sections or underutilized spaces, could accommodate bike corridors connecting major employment centers. Imagine cycling from South Philadelphia to University City entirely underground, safe from January ice and July heat.
Layer Two: Climate Resilience Infrastructure
Underground spaces maintain temperatures between 50-60°F year-round regardless of surface conditions. As Philadelphia faces increasingly severe heat waves, subway stations could function as public cooling centers during extreme weather, potentially saving lives among our most vulnerable residents.
Other cities have been more ambitious. Singapore has explored underground caverns for strategic fuel storage. China’s cities allocate subterranean layers for parking, utilities, and flood management. Philadelphia’s existing tunnels could house stormwater detention systems, capturing runoff during increasing flood events and releasing it gradually. The abandoned Arch Street Subway tunnel, that ghost of early 20th-century ambition, could be retrofitted for water management, turning a white elephant into environmental infrastructure.
The proposed Roosevelt Boulevard corridor, where subway construction will excavate millions of cubic yards anyway, presents an opportunity to build climate resilience from the ground up: not just tunnels for trains but integrated systems for stormwater management, geothermal energy storage, and emergency services.
Layer Three: Distributed Energy and Data
Every subway tunnel already houses electrical infrastructure. What if we treated this as the backbone of a distributed energy grid? Solar panels on station roofs, feeding batteries housed in climate-controlled underground vaults, could create neighborhood-scale microgrids providing resilience when surface infrastructure fails, as it did during various storms and disruptions in recent years.
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Similarly, unused tunnel sections could house data centers. Companies have experimented with cooling-efficient data centers in unconventional environments, including underwater; underground facilities offer similar thermal advantages without oceanic challenges. The heat generated by servers, currently wasted, could warm platforms during winter, while the servers themselves benefit from stable underground temperatures. Digital infrastructure and transit infrastructure, mutually reinforcing.
Layer Four: Urban Agriculture and Food Security
Underground and disused-tunnel farming is not science fiction but established technology, with pilot projects proposed or attempted in a handful of cities worldwide. London’s Growing Underground once cultivated salad greens 108 feet below the city in a converted World War II air raid shelter before the venture closed in 2023, a reminder that these projects, while promising, are not guaranteed to last without sustained investment. Still, the underlying model is worth testing here.
Philadelphia has roughly 60 miles of subway and trolley tunnels, plus abandoned sections like parts of the Arch Street line and ghost stations along the Broad Street corridor. LED grow lights powered by the grid infrastructure already in place, hydroponic systems fed by captured stormwater, climate-controlled environments perfect for year-round cultivation: these could produce fresh vegetables for neighborhood distribution, creating food security while employing local residents. The trolley barn at Woodland Avenue, where new Alstom Citadis cars will be maintained, could pilot integrated agriculture alongside vehicle storage.
Layer Five: Arts, Culture, and Public Space
Naples transformed its subway into “Art Stations”: a network of a dozen-plus stops on Line 1 and Line 6 filled with more than 200 commissioned works, ranked among the most beautiful transit stations in the world. Philadelphia, birthplace of the nation’s Mural Arts program, could follow suit ambitiously. Imagine commissioning works throughout the system that tell neighborhood stories, honor overlooked histories, celebrate Philadelphia’s firsts: the Slinky, the American flag, Wawa, our leadership in abolitionism and women’s suffrage.
We can go even further. The abandoned Arch Street tunnel could become performance space, underground theater echoing the speakeasies that allegedly operated in tunnels during Prohibition (urban legend, but compelling nonetheless). London’s Old Vic Tunnels, an underground space behind Waterloo Station, hosted art exhibitions and performances from 2009 to 2013, including the UK premiere of Banksy’s documentary “Exit Through the Gift Shop.” Other cities have floated similar ideas for their own abandoned transit tunnels, with proposals ranging from event venues to historical tours.
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Philadelphia’s ghost stations, Fisher’s Station in Logan, the sealed Adams Avenue station beneath Roosevelt Boulevard, the platform-less tunnel beneath Rittenhouse Square where wealthy residents once blocked construction, could become museums of democracy’s failures and aspirations, teaching spaces about equity and infrastructure, about who gets access and who gets left behind.
Layer Six: Emergency Services and Civic Infrastructure
When hurricane winds or civil unrest make surface movement dangerous, when infrastructure fails or disasters strike, subway tunnels provide protected corridors. Paris’s catacombs sheltered Resistance fighters during Nazi occupation. London’s Underground served as bomb shelters during the Blitz, housing thousands nightly.
Philadelphia should formalize this. Designated stations equipped as emergency shelters with stored supplies, medical equipment, communications gear. The consistent temperature and protection from surface conditions make underground spaces ideal for medication storage, emergency generators, even temporary hospital facilities. The Roosevelt Boulevard Subway design should incorporate emergency services from the outset: spaces for first responders, communication networks independent of surface systems, water access points.
Underground democracy
This vision sounds expensive. I can almost anticipate my friends who will cite SEPTA’s current deficit, Pennsylvania’s budget battles, and the Roosevelt Boulevard’s multibillion-dollar price tag. But hear me out.
Philadelphia’s current crisis exists precisely because we’ve treated infrastructure as expense rather than investment, as single-purpose rather than multifunctional, as something to maintain minimally rather than reimagine ambitiously.
The Roosevelt Boulevard Subway, built with integrated climate resilience, energy infrastructure, and community spaces, would cost more upfront but deliver exponentially greater value. Every dollar invested would serve multiple purposes, mobility and cooling centers and stormwater management and emergency services, just as every root in my AI-generated film anchors and nourishes and communicates simultaneously.
Funding mechanisms exist if we seek them. The federal infrastructure law of 2021 has directed funding toward transit accessibility projects nationally, Philadelphia included, though the region will need far more than any single federal allocation provides. The trolley modernization program, deploying 130 new Alstom Citadis streetcars with deliveries beginning in 2027 and running through 2030, demonstrates that major investments remain possible when the vision is clear and the benefits tangible.
State funding will require political will. New York’s MTA has grown weekday subway service by 2% since 2023, adding more than 160 daily trips, on the strength of Governor Hochul’s 2023 funding intervention. Pennsylvania has moved more slowly: lawmakers ultimately allowed SEPTA to raid its own capital budget rather than deliver new recurring revenue. Is this fiscal prudence or civic suicide? Is the solution accepting scarcity or changing the politics that create it?
Public-private partnerships could finance specific elements. Technology companies could invest in underground data centers that reduce their cooling costs while providing backup power for transit. Real estate developers benefit from transit-oriented development, residential and commercial projects near subway stations increase in value, generating tax revenue that can support infrastructure. Value capture mechanisms, where those who profit from improved transit help fund it, have financed systems from Hong Kong to Washington, D.C.
The 2026 Semiquincentennial creates urgency and opportunity for our city. As visitors flood Philadelphia, as global attention focuses on America’s birthplace, the city can showcase not just founding documents but founding principles translated into infrastructure. We can demonstrate that democracy means more than voting, it means building systems that serve everyone equitably, creating the physical networks that make liberty and justice something more than words.
Last word
What moved me to pitch the AI-generated film idea to my colleagues isn’t the fantasy but the mirror it holds to our failures. Nature, my film would suggest, wastes nothing. Every space serves purpose. Every structure multitasks. Every element connects to others in mutually reinforcing networks.
READ: The Review by Ajay Raju | The Long Gaze: From Paris to NY to Bombay (June 19, 2026)
Our subway system, by contrast, remains stubbornly disconnected from surrounding infrastructure, single-purpose in conception, underutilized in practice. We built tunnels for trains and stopped there, as if the immense effort of excavating and lining those passages entitled us to minimal ambition.
William Penn designed Philadelphia as a “greene countrie towne” where every citizen would have access to land and light. His grid became America’s template for rational urban planning, embodying Enlightenment ideals of order and accessibility. But Penn couldn’t foresee the vertical city, the layered metropolis where the most democratic spaces might lie beneath the street.
We can honor the Enlightenment ideals that birthed this nation by applying them to our underground: building systems that serve multiple purposes, creating infrastructure that promotes equity, investing in networks that connect rather than segregate.
The Declaration of Independence, signed here 250 years ago, asserted that all are created equal. But equality requires infrastructure, the physical systems that provide access, opportunity, mobility. When half of SEPTA’s riders earn less than $34,000 a year, when fares have risen 21.5%, when capital funds meant for modernization are borrowed to cover today’s operating shortfalls, we’re not merely facing a transit or budget crisis. We’re reneging on founding promises.
The roots are already there, waiting beneath our feet. The tunnels exist. The electrical infrastructure runs through them. The stations occupy prime urban land. We have already built the skeleton of a multifunctional underground network; we simply stopped before giving it life.
Philly, we can learn from what nature does with underground spaces and show the world what democracy does with ours.