A major phase in the dismantling of the world's first nuclear reactor in Cumbria has been completed.
Calder Hall, at Sellafield, was opened by the Queen in 1956
Calder Hall, which was opened by the Queen in 1956, ceased operating in 2003 after almost 50 years in service.
Part of the complex has been recommended to be turned into a national heritage site and museum.
Officials said more than a mile of asbestos cement pipe, 6,000 cubic metres of plastic packing and 260 tons of timber, have been removed.
The dismantling operation is being overseen by the recently-created Nuclear Decommissioning Authority (NDA).
A spokesman for British Nuclear Group, which manages the site, said: "The strip out of the internal materials from one of the towers has been successfully completed in preparation for the demolition of the four cooling towers."
He said the packaging had been cleared to be recycled and will be reused as plastic sewage pipe.
Dyan Foss, head of demolition delivery, added: "Work continues to progress well on the other three towers, and also on the preparation of the safety case that will be submitted to the Nuclear Installations Inspectorate for approval prior to this landmark demolition."
When it began producing electricity, Calder Hall, located on the existing Sellafield site, used what was then cutting-edge magnox technology.
But by the end of last century, its 196 megawatt capacity was considered too small to sustain its long-term viability.
It eventually closed in March 2003 with the then operator British Nuclear Fuels Limited (BNFL) blaming the move on the depressed electricity prices and high running costs.
A study has been commissioned into the costs and feasibility of preserving Calder Hall's number one reactor as a future heritage site and museum.