Cockermouth Castle is safe as a result of work taken following the December floods, Lord Egremont has said.
The floods triggered a landslide which washed away much of the vegetation under the grade one listed building which overlooks the River Derwent.
Leconfield Estates, which owns the castle, took advice from structural engineers to find the best way of protecting the ancient monument.
A contractor installed rock armour shortly afterwards, to protect the base of the embankment from further flood and erosion damage.
Lord Egremont was staying at his Cockermouth home this week.
He said: "We were worried after the floods but think it is secure now. We had to move very quickly but got all these stones in place and diverted the river.
"We hope the stones in the river will secure the area, I think enough has been done. It does look precarious but I think it's safe."
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