Europe

Chernobyl shelter safely placed over exploded reactor

  • A worker explains a structure of an arch-shaped enclosure in Chernobyl, Ukraine, Tuesday, Nov. 29, 2016. The gargantuan arch-shaped enclosure has begun slowly moving towards the exploded Chernobyl nuclear reactor, in what represents a significant step toward liquidating the remains of the world's worst nuclear accident. (AP Photo/Efrem Lukatsky)

    A worker explains a structure of an arch-shaped enclosure in Chernobyl, Ukraine, Tuesday, Nov. 29, 2016. The gargantuan arch-shaped enclosure has begun slowly moving towards the exploded Chernobyl nuclear reactor, in what represents a significant step toward liquidating the remains of the world's worst nuclear accident. (AP Photo/Efrem Lukatsky)  (The Associated Press)

  • A view of an arch-shaped enclosure, background, in Chernobyl, Ukraine, Tuesday, Nov. 29, 2016. The gargantuan arch-shaped enclosure has begun slowly moving towards the exploded Chernobyl nuclear reactor, in what represents a significant step toward liquidating the remains of the world's worst nuclear accident. (AP Photo/Efrem Lukatsky)

    A view of an arch-shaped enclosure, background, in Chernobyl, Ukraine, Tuesday, Nov. 29, 2016. The gargantuan arch-shaped enclosure has begun slowly moving towards the exploded Chernobyl nuclear reactor, in what represents a significant step toward liquidating the remains of the world's worst nuclear accident. (AP Photo/Efrem Lukatsky)  (The Associated Press)

  • Workers inspect the New Safe Confinement (NSC) movable enclosure at the nuclear power plant in Chernobyl, Ukraine, Tuesday, Nov. 29, 2016. The NSC enclosure has slowly begun to move towards covering the Chernobyl nuclear reactor, in what represents a significant step toward liquidating the remains of the world's worst nuclear accident. (AP Photo/Efrem Lukatsky)

    Workers inspect the New Safe Confinement (NSC) movable enclosure at the nuclear power plant in Chernobyl, Ukraine, Tuesday, Nov. 29, 2016. The NSC enclosure has slowly begun to move towards covering the Chernobyl nuclear reactor, in what represents a significant step toward liquidating the remains of the world's worst nuclear accident. (AP Photo/Efrem Lukatsky)  (The Associated Press)

A massive shelter has finally been installed over the exploded reactor at the Chernobyl nuclear plant, one of the most ambitious engineering projects in the world.

The half-cylinder-shaped shelter began being moved toward the reactor on a system of hydraulic jacks two weeks ago and reached its destination Tuesday, a significant step toward liquidating the remains of the world's worst nuclear accident, 30 years ago in what is now Ukraine.

Workers will now begin dismantling unstable parts of the original cover, the so-called sarcophagus, which was built over the reactor shortly after the explosion to contain radiation.

The new shelter is 275 meters (843 feet) wide and 108 meters (354 feet) tall and cost 1.5 billion euros, according to the European Bank for Reconstruction and Development.