(CNN) — Some call it the ghost town, because for decades it didn’t appear on any maps — a clandestine location that at the height of the Cold War likely concealed a deadly arsenal of nuclear weapons capable of wiping out major Western cities.

Others refer to it as the Polish Chernobyl, because the cloak of secrecy thrown up around its radioactive mysteries drew anxious comparisons to the exclusion zone surrounding the disaster-hit Ukrainian power station.

Reaching this town from Szczecin, the region’s capital, involves a long drive through Poland’s mostly rural lowlands, a terrain that also still carries the legacy of the Cold War.

Nowhere more so than the town of Drawsko Pomorskie, the location of the largest military training ground for NATO troops in Europe.

Last year, tens of thousands of military personnel poured into the area, making use of the cover offered by the landscape of lakes and dense forest for Defender-Europe 20, said to be the biggest military exercise on the continent for quarter of a century.

Head an hour further east from Drawsko, where the forest becomes deeper and quieter, and you’ll arrive at the former forbidden zone of Borne Sulinowo.

Mysterious town

The ruins of a former Soviet military hospital.

Malgosia Krakowska

Before the collapse of the Soviet Union in 1991, this place was accessible only for those with a special pass, or “пропуск” in Russian. Everyone else stayed away and pretended they knew nothing about it. It was closed, concealed and best avoided.

Nearly 12,000 Soviet troops were stationed in the Borne Sulinowo military complex at the height of the Cold War. They were part of the Northern Group of Forces present in Poland as part of the Warsaw Pact agreement between the Soviet Union and Eastern Bloc socialist republics.

”The place was a massive construction site for troops and military facilities,” Wiesław Bartoszek, owner of the local museum in Borne Sulinowo, tells CNN Travel.

“After 1945, when the Soviets took over the place, the complex had become part of the Warsaw Pact military plans, which included massive drills that prepared the ground and air forces for an invasion of the West.

”There was only one road leading there, one railway track ending up in the mysterious town behind electrified fences.”

People living near Borne Sulinowo were, apparently, too scared to even mention it.

Even before the arrival of the Soviets, the town had largely been off limits.

Prior to World War II, when the region was part of Germany, the town was known as Gross Born, and functioned as a military base and training ground. Adolf Hitler was photographed visiting in 1938.

In 1939, panzer troops stationed here under command of General Heinz Guderian launched the invasion of Poland that would trigger global conflict. Later it was used to house prisoners of war.

Adolf Hitler visited the German military base at Gross Born in 1938.

Keystone/Hulton Archive/Getty Images

The Germans built most of the infrastructure later used by the Soviets. There were barracks for troops, a railway and a huge military hospital complex that today stands abandoned, its remains an enigma waiting to be explored by visitors.

Security fences and barbed wire are long gone, leaving the abandoned grounds wide open to curious visitors. Visitors wander among trees and bushes that have sprung up around the skeletons of the remaining buildings.

Bartoszek says that the area is especially popular with tourists during the summer season. He likes to tell them the story of a mysterious tunnel that runs underneath the hospital, connecting a room used for dissecting human bodies to the railway. Researchers are still unsure what it was used for.

Nuclear warheads

Birch crosses mark the graves of soldiers who died after being incarcerated at Gross Born.

Vadim Pacajev/Sipa USA/AP

Nowadays, Borne Sulinowo is a residential district. After the Soviets left, the barracks were converted into apartments. The railway was removed and turned into the main road.

“People came to Borne from other parts of Poland because the apartments were very cheap,” says Bartoszek. About 5,000 people now live here.

Some of the functional buildings have been restored and refurbished over the years. A Soviet-era hospital is intact and has been renovated. Another H-shaped building in the town’s center is now a nursing home and rehabilitation unit for patients with multiple sclerosis.

The town still shows signs of its past, though. Some buildings, such as the grand structure that housed the old officers’ mess, are now decaying and in need of renovation. Marbled walls speak of their former glory.

While it may look like it’s seen better days, the town hopes to attract investors by marketing itself as a destination for tourists looking to explore the surrounding wilderness — and perhaps check out a piece of Soviet history.

The pine and oak forests are filled with lakes, streams, rivers and ponds and are ideal for cycling and hiking during the summer season. It’s also rich with wildlife including wild boars, deer and pheasants.

Driving this fascination are stories about nuclear warheads that once were hidden in massive silos in the area, one of three nuclear weapons facilities built in western Poland.

Rocket silos

Archeologists say Soviet nuclear warheads were stored here, ready for attacks on Western Europe.

Courtesy Malgosia Krakowska

The Soviet Union explicitly denied stockpiling nuclear missiles in Poland but archaeologists who researched the place by delving into archives of declassified satellite images and analyzing building scans are convinced otherwise.

”Some of the massive silos for these warheads are found near Borne Sulinowo in the village of Brzezńica-Kolonia,” says Bartoszek. “During the communist era, the zone was one of the best kept secret places in Europe.”

These storage chambers are now neglected and vandalized. Their concrete walls, covered in graffiti, are in surprisingly good shape but other installations or furnishings are missing. The storage chambers — approximately 70 meters long and 10 meters high — are buried under a thick layer of soil and covered with grass.

Bartoszek explains that the missiles were planned to be used as a tactical weapon, targeted at cities like Amsterdam and Paris. The power of the warheads varied from about 0.5 to 500 kilotons.

Now a museum, this bunker in Podborsko contains equipment apparently used to store nuclear warheads.

courtesy of Grzegorz Kiarszys. www.trzeciazona.pl

The construction of the massive silos for rockets was completed in 1969, funded in full by the Polish People’s Republic communist government according to the plans prepared by the Soviets.

”Only Russian troops could access the site,” Bartoszek says. “The whole area was excluded from the Polish jurisdiction. This was a de facto Russian territory.”

After the collapse of the Soviet Union and the end of the Warsaw Pact, all the maps documenting the place were destroyed.

Archaeologists like Grzegorz Kiarszys, an adjunct professor at the Institute of History and International Relations in Poland who is the author of the first in-depth study into the complex, have determined the location of the silos.

Kiarszys relied on declassified CIA satellite photos, ground-penetrating radar and checks for signs of radiation. According to his research, no contamination was detected.

Today, an emptiness looms over these abandoned and devastated buildings.

While the forests and lakes that surround them will hopefully soon, when the pandemic is over, offer relaxation for vacationers, these relics of totalitarianism and its nuclear ambitions will also serve as a reminder of a darker chapter in our history.

Malgosia Krakowska is Polish-born journalist who covers Poland for international news outlets.