Welcome back to Camera Obscura, Curbed's series of photo essays by Nathan Kensinger. This week, the complicated future of an old Bronx train route.

The old Port Morris Branch of the New York and Harlem Railroad runs like a hidden scar through the heart of the South Bronx. Dating back to 1842, this decommissioned train line has been a dumping ground for decades, with layers of pollution and neglect heaped along its route. Traveling below street level for two miles from Port Morris through Mott Haven, Morrisania, and Melrose, its history has always been murky to neighborhood residents, who have nicknamed different sections of the tracks The Bronx Swamp and The Hole, and over the years, the abandoned train line has been been variously described as a "bug-infested basin," a "blight on the community," a "filthy concoction of standing water and garbage" and a "needle ridden Bronx drug den." But after a recent city-sponsored cleanup, the future of the Port Morris Branch has been brought back into the spotlight.

In September 2015, a homeless camp and heroin shooting gallery along the train line were cleared away by bulldozers as part of a citywide cleanup, prompting Bronx Borough President Ruben Diaz Jr. to write an open letter to the mayor, suggesting the Port Morris Branch should be redeveloped as a subterranean, Lowline-style park. "Such a project would connect Mott Haven with Melrose with new open space," wrote the Borough President, "and would be a model for the future reuse of the many miles of essentially abandoned railway that is spread across the five boroughs." The idea of a Bronx Lowline quickly made headlines around the city, and just as quickly led rail advocates to call for the Port Morris Branch to be reactivated. In the ensuing stories about the train line, however, there has been widespread confusion about the current status of the Port Morris Branch.

Any plan to convert sections of this unused train line into public parklands would require millions of dollars and the cooperation of the landlords who control it. Most publications have identified the railroad company CSX as the owner of the entire train line, an ownership situation that presents a "major road block" in which the land "would have to be bought or seized by the city." The ownership of the Port Morris Branch has been a murky issue for years, as the city discovered while attempting to collect payment for a 2009 cleanup. But online property records reveal that today, the various sections of the Port Morris Branch are actually owned by several smaller companies, including Pinnacle Real Estate Ventures, which has offices in Jamaica, Queens.

"We are the deedholder of several portions of the trench," Joshua Dardashtian, the president of Pinnacle Real Estate Ventures, said in a recent email. As part of Pinnacle Real Estate, Dardashtian also serves as the president of South Bronx Revitalization, a company that bought several different sections along the northern part of the train line in 2006. "We purchased it from a California based railroad trust," wrote Dardashtian, who was present at the recent cleanup along the tracks. He said he had not yet been contacted about the idea for creating a park along the train line, and was not aware of that proposal's existence before we spoke. His company, however, has been actively developing their parcels of land on the Port Morris Branch. "Several of the parcels have already been incorporated into some of the major projects in the area, including Via Verde and Bronx Commons," wrote Dardashtian. "There has been preliminary planning for additional residential, retail, and community use development for other parcels."

The fact that Via Verde, an award-winning residential complex, has already been built on a large section of the middle of the Port Morris Branch would seem to preclude the possibility of reactivating the original train line here. Its buildings would have to be demolished in order to return the trackbed to service, displacing hundreds of tenants. But what of the remaining sections of the train line? Could a park actually be built there? A recent walk along its length revealed several places where, in theory, separate sections of non-contiguous parkland could be created. It also revealed that, as the details of the Lowline proposal are worked out, homeless encampments and drug users have slowly been returning to the Port Morris Branch.

The train line, sunken down below street level except at its two ends, is currently accessible via a handful of entrance points, where fences have been peeled back and makeshift staircases are built down to the trackbed with pallets and pipes. Near these entrances are active homeless encampments and hundreds of used syringes. "I'm homeless. I don't got nowhere to live, so I live down there," said one resident of The Hole, the area near the center of the train line which was bulldozed during the 2015 cleanup. Although he preferred to remain anonymous, the homeless resident said he had lived along the tracks since 2005, and that others had lived there for much longer. "Is it safe? You could walk down there," he said. "There's nobody down there going to rob you, steal from you, shoot you."

The last time that the Port Morris Branch was in the news was 2009, when the city attempted an even more ambitious cleanup in a southern section of tracks known to locals as the Bronx Swamp. This flooded, neon green waterway in Mott Haven had plagued the neighborhood with swarms of mosquitos for years, until the Department of Environmental Protection regraded a section of the train line and pumped out 650,000 gallons of water. A walk along this same section of the Port Morris Branch today shows that little seems to have changed since 2009. The trench remains covered with debris, including condoms, broken bicycles, rusted air conditioners, and discarded bibles, and the tracks are still blocked by flooding, although the water is now hidden in a tunnel beneath a public park. Both the park and tunnel are also littered with dozens of empty syringes.

There are only two street-level entrances to the Port Morris Branch, located at either end of the train line, and each has been blocked off by industry and fences. Its southernmost end in Port Morris is used to store run-down, graffiti-covered construction equipment, while its northern end in Melrose contains a vast tow yard, clogged with crushed cars and destroyed taxis. Here, the terminus of the train line is gated off and covered in razor wire. "For the past 10 years that I work here, it's been closed," said Ide, who owns the Double O towing company at the tracks' terminus. "Sometimes the city comes to inspect the bridges, and we unlock the gates." Ide had also not heard about the proposal to create a park on the train line, but thought it could be a good idea. "That would be nice. Maybe I would go down there myself sometimes."

In the aftermath of the High Line, there has been a surge in popularity for ideas to redevelop New York City's abandoned train lines, from the MTA's recent call for proposals for the decommissioned Montauk Cutoff, to the QueensWay along the old Rockway Beach Branch. These outer-borough tracks, however, bear only a passing physical resemblance to Manhattan's High Line, which currently cuts through some of the most expensive real estate in New York. Any proposals for the crumbling, neglected train lines in the Bronx, Queens, or Staten Island, which cut through a complicated web of industrial and residential neighborhoods, will demand much deeper investigation.

Near East 165th Street, the northernmost end of the Port Morris Branch intersects with the Metro North tracks, beneath a complicated intersection of streets.

The train line once ran through this open space, now home to the Double O towing company, which is surrounded by old warehouses. Neighboring businesses include a building material lot, a self-storage warehouse, and a Days Inn hotel.

The old train line, underneath East 163rd Street, is blocked off by a horde of damaged cars and taxis and a locked gate. The tow yard is owned by American Pen Corp, according to public documents.

Through the razor wire and chainlink, the northern stretches of the Port Morris Branch are visible. The tracks in this northern section are littered with downed trees and household debris.

Looking south down the tracks from under the East 163rd Street bridge, which is maintained by the city. The section of tracks between the bridges is owned by South Bronx Revitalization, according to public documents.

An encampment along Brook Avenue, where homeless residents have created an access point to the old train line. The Bronx Commons project, "a 361,600 square foot mixed-use development," will be built at this site.

This construction site, bordering the Port Morris Branch at Elton Avenue and East 161st Street, will become a 12-story residential tower as part of the larger Melrose Commons development project.

From 161st street, the train line continues south through the neighborhood, below street level, passing by several familiar landmarks, including Boricua College at Melrose Commons, the old Bronx Borough Courthouse, the 42nd Police Precinct, and the Rincón Criollo casita.

At Via Verde, near East 156th Street, the tracks reach an impasse, with residential buildings and a private courtyard built directly into the track bed. It would be difficult to route a reactivated train line around this complex.

A former homeless camp, covered with used needles, can be found at the south side of Via Verde, where the tracks abruptly stop.

The old train line here is sunken down only a few feet below street level and borders several high schools and athletic fields, making it potentially one of the easiest places to build a park. This long section of the train line is also owned by South Bronx Revitalization.

Hundreds of used syringes can be found along the tracks here, which have been used as a heroin shooting gallery for many years.

The tracks continue south of Westchester Avenue, through the area known as The Hole, the longtime homeless encampment and heroin den which was recently cleared out by the city, sparking media coverage of the Port Morris Branch. This segment of tracks is, again, owned by South Bronx Revitalization.

A new $70 million police precinct is scheduled to be built in the fenced off area above The Hole, at East 149th Street. The tracks continue south from here, underneath St. Mary's Park, which is also littered with used heroin needles.

In the tunnel beneath St. Mary's Park, the tracks are flooded and impassable after a recent snowfall. This tunnel was built in 1905 and, like all of the bridges and tunnels along the line, is under the care of the city government.

If a park were built in this section of tracks, it would be more comparable to the eastern end of the Coulée Verte in Paris, a project which was the predecessor and inspiration for the High Line. Here, foreboding subterranean tracks and tunnels were successfully transformed into a unique collection of bike lanes, paths, gardens, and fountains, all hidden underneath a lush green canopy.

Today, the open air sections of track near East 144th Street are used as a parking lot for a construction company, with graffiti covered trucks and equipment lining the trackbed for several blocks. Evidence of homeless camps and drug use are scattered around this area, which is owned by Metropolitan 47th LLC, according to public records.

This long stretch of tracks was formerly known as The Bronx Swamp because it was permanently flooded. After a 2009 cleanup which regraded its surface, much of the line is now walkable. Sections of track here are owned by Metropolitan 47th LLC, and by Concord-Wales LLC, according to public records.

A view of the Bronx Swamp from 2009, before it was drained. The tracks here have long been a lure to Urban Explorers and photographers, including the LTV Squad and James and Karla Murray, who recently published a collection of their older photographs from the Port Morris Branch on Untapped Cities.

The train line here is now covered with household debris from the bordering apartment buildings, although the $350,000 cleanup in 2009 removed tons of debris from the area.

Near the southern end of the Port Morris Branch, underneath Bruckner Boulevard, the old train tracks are still in place. From here, the tracks continue down to the East River, in an area used for parking lots and storage warehouses.

· Nathan Kensinger [Official]

· Abandoned South Bronx Rail Tracks Could Become a Park [Curbed]

· Camera Obscura archive [Curbed]