Written by Oscar Holland, CNN

When photographer David McMillan first visited the city of Pripyat in 1994, he expected his movements to be restricted. Just eight years prior, a reactor at the nearby Chernobyl Nuclear Power Plant had exploded, forcing a region-wide evacuation and sending radioactive fallout billowing across Europe.

Yet, the photographer was not only free to roam the 1,000-square-mile Chernobyl Exclusion Zone -- which remains largely uninhabited to this day -- he was able to get within meters of the damaged reactor.

"The challenge was finding people who could get me in," he recalled in a phone interview. "I didn't know where to go; I was at the mercy of drivers and my interpreter.

"I had no real sense of (the danger)," he added. "People just advised me that some areas were heavily contaminated, and that I should maybe only take a minute or two to photograph there."

McMillan's images to the Chernobyl Exclusion Zone reveal eerily abandoned buildings. Credit: Courtesy David McMillan

This initial trip resulted in a series of eerie images documenting derelict buildings, overgrown playgrounds and vehicles abandoned after the cleanup. It also sparked a curiosity that, over the next quarter-century, would bring the Canadian photographer back to the region more than 20 times.

Now, 200 of his photos are being published in the forthcoming book, "Growth and Decay: Pripyat and the Chernobyl Exclusion Zone." They provide an astonishing look at a ghost city largely untouched since the disaster, while exploring the enduring power of nature and the inevitability of decline.

Remains of a 'showcase' city

Pripyat, in present-day Ukraine, was part of the Soviet Union at the time of the catastrophe in April 1986. Built in the previous decade to serve the power plant and its workers, the city was once home to around 50,000 people

"It must have been beautiful," said McMillan, who has studied archive images of the area. "It was considered, at the time, to be one of the finest cities to live in the Soviet Union. There were lots of schools and hospitals, and facilities for sports and culture, so it was kind of a showcase city."

These amenities now lie abandoned, having fallen victim to decay, rust and looting. Many of McMillan's photos -- whether showing empty swimming pools or deserted churches -- reveal just how suddenly the city was evacuated.

McMillan shot the same spot multiple times. Credit: Courtesy David McMillan

"In the schools, it felt like it would have if the students had just left for the afternoon," he said. "There were still teachers' record books, textbooks, student artwork and things like that."

The buildings thus served as time capsules, of sorts. Images showing faded portraits of Marx and Engels, or the bust of Lenin in an unkempt yard, capture a particular moment in political history.

But they also demonstrate the power of time. In some cases, McMillan photographed the same spot multiple times, over the course of many years, to highlight the deterioration of the built environment.

One of the most powerful examples is a series of images taken in a kindergarten stairwell. The first, captured in 1994, depicts brightly-colored flags of the former Soviet republics affixed to a peeling wall. By the time of the latest photograph, taken last November, just one remains -- and it has been damaged and discolored beyond recognition.

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"If you came upon it, you wouldn't know what it had been; you wouldn't even see that it might have been the representation of a flag," McMillan said. "It seemed to me symbolic of the way our own memory of the Soviet era is vanishing into history."

Photos of playgrounds and slides also provide pertinent symbols of time's passing. The children that once played there will now be in their thirties or forties.

"Going into some of the kindergartens, where there were so many remnants of the children -- and knowing that the incidence of thyroid cancer has spiked because of the accident, triggered a different sort of (emotional response).

"But there's probably an unavoidable -- and I'm reluctant to say this -- beauty (to the decay)," he added. "I've found that the walls have sort of ripened."

Nature's return

As his book's title, "Growth and Decay," suggests, McMillan is concerned with both the retreat of humankind and the reappearance of nature. Landscapes in his photos, while bleak, feature blossoming plants and trees bursting through manmade structures.

"People weren't around, and when nature wasn't being cut back and cultivated, it just grew wild and reclaimed itself," the photographer said. "I guess it was heartening to see this kind of regrowth, and inevitable to see culture vanishing."

"There has been a repopulation of animals, and someone even told me that the birding (bird watching) there is among the best in Europe."

Plants and trees have regrown in some of the buildings. Credit: Courtesy David McMillan

McMillan's images also feature portraits of people he encountered within the Exclusion Zone, including engineers, laborers and scientists hunting wildlife to measure radiation in their organs. One image, taken in 1995, shows a woman returning to her village to clean ancestral graves.

Having met so many returnees, McMillan is relatively relaxed about the possible implications for his own health. Now 73, he typically visits for a week at a time, meaning that he has spent months -- cumulatively -- inside the Chernobyl Exclusion Zone.

One of his original guides has contracted lymphoma since leaving Ukraine for Canada, though the photographer said it's unclear whether radiation is to blame.

"The thing about radiation is that it's intangible," McMillan said. "When I did bring a dosimeter with me on one occasion, (the radiation levels) were so irregular. They weren't the same throughout the Exclusion Zone -- it's very variable."

As contamination lessens with each passing year, so too does the risk, the photographer explained. A newly built "sarcophagus" (known as Chernobyl New Safe Confinement) now encases the reactor, replacing the temporary concrete wrapper first erected in 1986 to contain the fallout.

Tourists are also an increasingly common sight, according to McMillan, who sometimes encounters buses on day trips from Ukraine's capital Kiev. Last year, a group of artists even staged a rave in Pripyat, with the site quickly becoming what the photographer called a "black Disneyland of sorts."

"There are people living in some (nearby) areas that are less contaminated, so I've never worried," he said.

"Now, a more real hazard is that the buildings are collapsing. They seem delicate sometimes, (and) when you're walking through them, you just don't know what could happen."

This article was updated to reflect that the population of Pripyat was once home to around 50,000 people. The gallery was updated to remove one of the images because it unintentionally showed graffiti with derogatory language.