Pripyat, Ukraine (CNN) -- There's an eerie stillness about the desolate buildings and empty streets of Pripyat. From the main square, overgrown with brambles and wild grass, the town looks like an ancient ruin lost in a jungle. Buildings, windows smashed, stand like monolithic giants peering down. On one, an unlit neon sign saying "restaurant" clings onto a rooftop. From another, a hammer and sickle looms over the scene below. I can't think of a single place I've visited that feels so utterly abandoned and lost. The order to evacuate Pripyat came too late. It had been 36 hours since an explosion in Reactor 4 at Chernobyl, on April 26, 1986, had spewed its radioactive debris over the town.
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Ukrainian city remains a ghost town 25 years after Chernobyl
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Tourists are now allowed into the exclusion zone
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Estimates of the disaster's death toll vary widely
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Mikhail Gorbachev says the disaster contributed to the Soviet collapse
On several occasions since, Gorbachev -- remembered for his perestroika and glasnost reforms -- said he believed @placeholder was equally responsible for bringing about the collapse of the Soviet Union.