The Liquidators

The Soviet Union sent 600,000 to 800,000 workers called "liquidators" to contain the disaster. Many worked in 90-second shifts on the reactor roof because longer exposure meant death. Robots failed because radiation fried their electronics within minutes.

A massive concrete sarcophagus was built over the reactor in just 206 days. By 2016, it was crumbling, so a new EUR 1.5 billion steel containment structure was slid into place — the largest movable structure ever built. Chernobyl's cleanup isn't finished. It may never be.