A sign warns of radiation contamination near abandoned apartment buildings on April 9, 2016 in Pripyat, Ukraine. Pripyat, built in the 1970s as a model Soviet city to house the workers and families of the Chernobyl nuclear power plant, was evacuated following the April 26, 1986 disaster, and is now a ghost town. The world is commemorating the 30th anniversary of the April 26, 1986 Chernobyl disaster.(Sean Gallup/Getty Images)

To many, it's difficult to imagine that the city of Pripyat, Ukraine was once home to 45,000 people. It's now a ghost town, with itshigh-rise apartment buildings, hospital, shops, schools, restaurants, cultural center and sports facilities now crumbling in decay and overgrown with trees. It's also one of the most famous areas in the Chernobyl Exclusion Zone,a restricted zone contaminated by radiation from the April 26, 1986 meltdown of reactor number four at the nearby Chernobyl plant, a meltdown that spewed radiaoactive fallout across the globe and is considered the world's worst civilian nuclear accident.

As the world commemorates the Chernobyl disaster's 30th anniversary, tourists continue to explore certain portions of the exclusion zone, where approximately 90 villages were evacuated and abandoned after the disaster. Tourists jointours of Pripyat's eerie, abandoned buildings, taking photos of rusty rides in the abandoned amusement park and roaming through what used to be the city's main square. Reports say Pripyat, which was built in the 1970s to house workers of the Chernobyl plant, is safe for tourists to visit for a short amount of time. But for many still living in the region near the borders of Ukraine and Belarus, the effects of the worst nuclear disaster in history will stay with them forever.

In Ukraine, thousands of people still live in regions believed to be contaminated with radiation from the 1986 disaster. One of the greatest concerns for these residents is the effects ofcaesium-137, which is able topass through the food chain and contaminatemilk, fish and other food products, according to Greenpeace. Many inhabitants over the years have continued to eat fruit and vegetables, fish, mushrooms and berries cultivated in areas that had become contaminated following the accident.

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Many of the villages in the exclusion zone, like Pripyat, barely exhibit any signs of life. A memorial to Soviet soldiers killed during World War II is nearly all that remains of the village of Besyadz, Belarus, which was once home to 150 families. In Bartolomeyevka, also in Belarus, only four residents still remain. Authorities concentrated their initial evacuation efforts on communities closer to Chernobyl, but by the early 1990s, they determined Besyadz, Bartolomeyevka and other nearby villages were not safe, evacuated the residents, razed nearly all structures and buried the ruins.

While the exclusion zone remains silent, voices—and stories—of Chernobyl can still be heard inSlavutych, Ukraine.Slavutych is a new town built in the years after the Chernobyl accident to replace Pripyat. It is home to men and women who still work at Chernobyl.The Chernobyl plant, which houses not just stricken reactor number four but three other reactors that continued to operate after the accident, is in a long-term decommissioning process and still employs approximately 3,000 people. Slavutych is also home to many Chernobyl "liquidators,"a corps of soldiers, firefighters, miners, and volunteers who were called for cleanup in the days and weeks after the disaster.

One such "liquidator" is Lyudmila Vyerpovskaya, 74, who worked in the construction department at the Chernobyl nuclear power plant and was in a nearby village on April, 26, 1986 when reactor number four exploded. She said that when she returned on April 28, evacuation of Pripyat had begun, and the city was in chaos. "It was like war had broken out and [the people] were refugees," she told Getty Images.

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Vyerpovskaya recalledbuses stopping and people stepping out to vomit, likely from the radiation that was seeping into the city. In the weeks after the accident she helped to administer the evacuation, creating lists of evacuees and their destinations and filing reports to authorities. Later, she returned to the plant and worked on repairs and reconstruction in the three remaining (and still active) reactors. Despite her exposure to radiation at the time, she says she is in good health.

Another "liquidator," Pavel Fomin, 59, was a plant safety manager at the plant and was fishing with a buddy at the nearby Pripyat River in the early hours of April, 26, 1986. He said he hurried to the plant and found the dosimeters designed to warn of radiation-level increases were all "showing red" and stopped functioning completely days after. "They just weren't designed for such high readings," Fomin said.

His wife and two children were eventually evacuated but Fomin stayed on, helping with radiation-level monitoring once military-grade dosimeters arrived. He says blood tests showed that his children each received a dangerously-high dose of 60 roentgens of radiation from exposure before their evacuation. His daughter later had a son who was born with an open stomach, though he was saved by surgeons in a Kiev hospital. Fomin said he has developed a heart rhythm disorder and has undergone surgery for cataracts, a condition common among Chernobyl liquidators.