For many years, the Brooklyn Navy Yard has been a forbidding presence along the East River waterfront, hidden from the surrounding neighborhood behind walls and fences, with warning signs along its perimeter blaring out antiquated threats: This Installation Patrolled by Military Working Dogs! It Is Unlawful To Enter Without Permission Of The Commanding Officer! Security checkpoints block every entrance to the yard, while inside, patrol cars circle constantly and a security booth is set up at the MTA bus stop to check the identification of anyone disembarking. This month, however, several new projects are cracking open these barriers and granting the public access to parts of the Navy Yard that have been unseen for decades.

The first of these projects launched this past weekend, with the premiere of Creative Time’s new public art project Fly By Night, created by artist Duke Riley, and the opening of The Gatehouses, a new bar and cafe space operated by the Kings County Distillery. On a recent night, hundreds of visitors lined up outside the Sands Street gate, waiting to enter the yard and walk out to the rarely-seen waterfront to experience Fly By Night, an installation where a flock of 2,000 pigeons equipped with LED lights appear like fireflies at sunset, soaring overhead into the darkening sky to create complex constellations. After the performance, many attendees stayed on at the yard to sip cocktails inside one of the old Sands Street gatehouses, which had been closed off and abandoned for the past 40 years. These historic structures will now be accessible year round, and will soon be joined by another unique public space when the grounds of the Naval Hospital Cemetery open on May 20th, becoming part of the Brooklyn Waterfront Greenway.

A visit to Fly By Night and The Gatehouses provides a good opportunity to reflect on the changing landscape of the Brooklyn Navy Yard. Just ten years ago, much of the yard was dominated by a collection of derelict and anonymous military structures, known only by their building numbers. Building 268 - a mostly empty warehouse exposed to the elements. Building 128 - an enormous, hulking ruin filled with debris. Building 121 - a dusty burial shroud manufacturer filled with partition walls and drop ceilings. Many of these buildings have since been reclaimed and renovated by the Brooklyn Navy Yard Development Corporation (BNYDC), as part of their ongoing process of redevelopment, and have been renamed by their new tenants: the Dugall Greenhouse, the Green Manufacturing Center, the Kings County Distillery at the Paymaster Building.

As part of this same process, the BNYDC has slowly opened up the yard to the public, allowing open studio days, building a visitor center and museum at BLDG 92, and supporting a full slate of historic tours led by the talented guides at Turnstile Tours. The Gatehouses, the Naval Cemetery Landscape, and Fly By Night represent the next steps in this process of allowing more visitors into the yard. "This is certainly, as far as I know, their first large-scale public art project," said Katie Hollander, the executive director of Creative Time. "The Navy Yard is kind of like a gated community. You can’t access it unless you are invited or on the list, and so it does have this mystique about it. It’s still very old world, in terms of the companies and the businesses and the employees down there, but then it also has all these new tech and design companies that are moving in, so it’s a real merge of both old and new."

Of course, these projects are just a few of the many significant changes scheduled for the Navy Yard. Earlier this May, ground was broken at Dock 72, where an enormous 675,000-square-foot building will rise next to the iconic cranes of the GMD Shipyard, becoming a home for the office-sharing company WeWork. Nearby, renovations are almost complete at Building 128, which will become part of the Green Manufacturing Center and a home to Mast Brothers Chocolate, and at Building 77, where Russ & Daughters will take 14,000 square feet of an enormous 16-story structure. Meanwhile, over at Admiral’s Row, a collection of historic, neglected 19th century houses, demolition equipment is now in place, and the homes will soon be destroyed to make way for a parking lot adjoining a new Wegmans grocery store. These new developments will bring thousands of new visitors and tenants to the Brooklyn Navy Yard, and will create a radically different landscape than today’s relatively quiet haven for pigeons, cemeteries, dry docks, and abandoned buildings.

Along the Flushing Avenue edge of the Brooklyn Navy Yard, the long-abandoned buildings of Admiral’s Row now await the wrecking ball, surrounded by a verdant and wild forest. Despite the efforts of numerous preservation groups, most of these homes will soon be destroyed.

The walls along Flushing Avenue have been a substantial, impenetrable barrier between the neighborhood and the Navy Yard for decades. They will also soon be demolished, to make way for a parking lot and Wegmans grocery store.

At the opposite end of the yard, the fenced off Brooklyn Naval Hospital campus also contains a long-abandoned collection of buildings. A section of fence here will soon be removed, to allow public entrance to the Naval Hospital Cemetery.

A system of raised paths is being constructed above the cemetery’s grounds. Beginning in 1831, more than 2,000 military service personnel were buried here, according to a sign placed on site. Most were disinterred in 1926, but some remains are still located in the grounds.

At the Sands Street gate, the historic gatehouses are now open to the public after sitting empty for 40 years. "They were just full of lots of dust and debris," said Brianna Halstead, of the Kings County Distillery, which leases the space from the Navy Yard.

The distillery has opened a tasting room, bar, and cafe in one of the gatehouses, after renovating the space. "We didn’t know what was underneath, or what we could salvage, but you can see that we tried to keep as much of it intact as possible," said Halstead. "We were really excited to revitalize it."

The Gatehouses serves Parlor Coffee in the morning, sandwiches from Vinegar Hill House during the day, and cocktails made from the distillery’s whiskey in the evening. "Our license only allows us to sell New York State products."

Just inside the Sand Street gate, the distillery operates out of Building 121, the Paymaster Building, which dates back to 1899. Kings County Distillery moved here in 2012.

The upper floor of the Paymaster building, as seen in 2010. "There was a funerary shroud manufacturer here," said Halstead. "They had all the windows blocked off upstairs. It was all very dark."

The building now houses the distillery on the ground floor and a micro-museum, for tours and tastings, on the upper floor. "We opened it up," said Halstead. "We do tours every Saturday and we get 150 to 200 people coming through during those times."

Further into the yard, the renovation of Building 128 is nearing completion. This structure, completed in 1899, was once used to fabricate and assemble engines and other ship parts.

Work is still being completed on the interior of Building 128, which will become part of the Green Manufacturing Center, a 220,000-square-foot complex.

In 2008, this same structure was in much worse condition, missing roof panels and windows, and filled with debris, including abandoned baseball cards and toys.

Another 2008 view of a section of the Green Manufacturing Center. Creative Time recently held their annual gala in a renovated section of these buildings. "We had over 500 people come to the gala," said Katie Hollander, "at the new Mast Brothers space in the yard. That was really fun, to be able to activate that space for the first time."

Building 268, now known as the Duggal Greenhouse, is a 35,000-square-foot warehouse that recently hosted the Democratic debate between Hillary Clinton and Bernie Sanders.

Prior to its re-opening in 2013, the building, seen here in 2010, underwent a huge renovation to remove asbestos and replace missing windows, walls, and floors.

Before the renovation, it had been an underused storage space, located directly adjacent to a wastewater treatment plant.

The building is now used as an event space, and claims that its first tenant after re-opening was Beyonce, who used it as a rehearsal hall.

Visitors to Creative Time’s Fly By Night installation walk past the Paymaster Building and down a street located next to the Duggal Warehouse, passing by a number of historic structures.

Fly By Night takes place on the waterfront near historic Drydock One, behind the Agger Fish Corp. warehouse, near an area that once housed a smaller-scale art installation by artist Lisa Kirk, a time-share shanty titled House Of Cards.

An old naval vessel, the Baylander, will house the pigeon coops during the duration of Fly By Night. Audience members are situated on bleacher seats, facing out over the ship and into the East River.

As the sun sets and twilight begins, Duke Riley and his team start to roust the pigeons from their coops using flags, whistles, and shouts. The pigeon handlers’ performance is central to the experience of Fly By Night.

With LED lights attached, these 2,000 birds create unique patterns in the sky. Domesticated pigeons have a long history in New York City, including a brief stint at the Navy Yard.

"The Brooklyn Navy Yard station possessed over 200 birds at its peak," according to a history written by Andrew Gustafson of Turnstile Tours, but the birds were decommissioned in 1901.

Against a dark sky, the pigeons resemble clusters of stars. "For us, the goal is really to allow for as many people as possible to experience this project, and feel inspired by this sense of wonder and joy that I hope this project brings to the city," said Katie Hollander.

Nathan Kensinger is a photographer, filmmaker, and curator who has been documenting New York City's abandoned edges, endangered neighborhoods, and post-industrial waterfront for more than a decade. His Camera Obscura photo essays have appeared on Curbed since 2012.