A multimillion-pound plan has been announced to protect a view at Blenheim Palace that was once described as the "finest in England".
The stately home will be removing 400,000 tonnes of silt from two lakes to protect a Grade I-listed bridge.
The view of the lakes and bridge was once described as the finest in England by Lord Randolph Churchill.
But Blenheim Palace said both lakes are now so shallow they risk drying out, which would threaten Vanbrugh Bridge.
"There is an absolute certainty that, if we do not do something radical soon, the view will be lost forever," head of estates Roy Cox said.
"This will be one of the largest civil engineering projects ever undertaken at a stately home... We will be removing enough silt to entirely fill Wembley Stadium."
The lakes are less than 11in (30cm) deep in 70% of their upper areas and will be returned to their original depth of about 6ft 5in (2m).
The work will start in 2018 following initial investigation work this year and will have to be completed in a period of about 20 weeks.
That is to ensure further damage is not caused to the bridge, which was designed by John Vanbrugh and built between 1708-1710.
Blenheim Palace expects the project will reveal hidden architectural features of the bridge, like flooded rooms, that have been underwater for 100 years.
Lord Randolph Churchill, father of Sir Winston, reportedly said it was the "finest view in England" in 1874 as he passed through the Woodstock Gate with his new wife.