Queen Street Mill, Burnley is temporarily closed because of the dangerous condition of an adjacent building.
Burnley Borough Council has cordoned off the neighbouring building, which is not owned by the county council, because of the condition of its chimney.
The decision has been taken to close Queen Street Mill as a precautionary measure to ensure the safety of people working in and visiting the museum.
The museum is expected to remain closed until the chimney on the neighbouring building has been made safe.
Queen Street Mill will therefore not reopen until this situation is resolved.
For more information visit www.lancashire.gov.uk/museums