Oxford's crumbling Castle Mound has been covered with plastic sheeting to protect it from heavy rain.
Last Wednesday, safety fencing was put up along the pavement in New Road which borders the ancient monument after earth started to slip two days earlier.
There were further minor landslips on the 11th century mound over the weekend.
Martin Brain, Oxfordshire County Council's principal engineer, said: "A protective sheet was put on the area of the mound where slippage has occurred.
"With the forecast for heavy rain on Sunday we felt it would give added protection.
"We hope to embark on discussions with experts this week in terms of a more permanent way forward.
"There was minor slippage towards the bottom of the mound over the weekend, but other than that there has been no significant movement since the middle of last week."
County council leader Keith Mitchell has described the mound, which was closed to the public last Wednesday, as "an Oxford icon" and pledged to fund any necessary repairs from the council's property budget.
The boundary wall that separates the mound from New Road collapsed on to the pavement in 1971 and was replaced by a reinforced concrete retaining wall.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article