大象传媒

It was the world's worst nuclear disaster. Yet 25 years on, no permanent safety shelter has been built to contain the radioactive core of the destroyed Chernobyl power plant. The accident took place in the early hours of the morning on April 26th, 1986. In the immediate aftermath, a temporary sarcophagus was built to contain the melted nuclear fuel rods - but this was meant to last just ten years.

On One Planet this week, reporter Richard Hollingham travels to the heart of the disaster, getting within meters of the reactor core. Along the way we meet the engineers trying to build a huge new shelter to protect the site for 100 years - but who've only got half the required money. Plus we go within the control room of Reactor Four - the place where horrified workers will have first realised a disaster was unfolding.

Also in the show, we hear about the long term effects of radiation on wildlife, and visit the abandoned town of Prypiat that sits just 3km away from the Chernobyl power plant.

As ever, tune in, have a listen and let us know what you think. Email the team at oneplanet@bbc.com, or join us on Facebook, the link's below. And don't forget we've a wealth of other material for you, including videos and photos from our trip to Chernobyl. All the links are below.