After Reactor No 4 exploded at the Chernobyl nuclear plant in Ukraine, the surrounding area became extremely contaminated. It has taken nine years to complete a structure to contain the radioactive material.
A new structure built to contain contamination at the Chernobyl nuclear plant was recently previewed to the world as it reaches completion.
Chernobyl was the site of a serious nuclear power accident that destroyed one of the plants' reactors on April 26, 1986, expelling radioactive material into the atmosphere.
Known as the worst ever in human history, the nuclear accident forced some 200,000 people to evacuate the vicinity.
Pripyat, a neighbouring town where many of the reactor's workers lived, became a ghost town.
The new structure to contain the contaminated site is the largest movable land-based structure ever built, spanning 257 metres, making it tall enough to house London's St Paul's Cathedral or Notre Dame de Paris.
It's a part of a Chernobyl safety project on behalf of the European Bank for Reconstruction and Development.
The entire project cost around €2.1 billion with funding from over 40 countries, including the European Union.
The landmark structure, called the New Safe Confinement, has been in the works since 1997 when a fund was set up to help Ukraine to make a stable and safe shelter over the building.
Taking nine years to build, the structure is set to issue a formal notice of completion soon.