Idris Evans at the memorial to the Ladies of Llangollen
An appeal has been launched to raise £30,000 to restore the memorial and tomb of the Ladies of Llangollen, in a churchyard in the Denbighshire town.
The tomb of the two aristocrats who eloped from Ireland in 1778 and lived together in north Wales for 50 years, has fallen into disrepair.
The Llangollen Historical Society is hoping to raise the money needed through grants and donations.
Old film of life in the town will be screened at an event to raise money.
Lady Eleanor Butler and Sarah Ponsonby scandalised high society in the 18th Century by leaving Ireland against their families' wishes and setting up home in north Wales.
They moved into Plas Newydd transforming the house and garden and spent their time reading, studying foreign languages and entertaining well-known figures of the day including the Duke of Wellington and the poet William Wordsworth.
Lady Eleanor Butler died in 1829 and Sarah Ponsonby died two years later.
They were buried in the church of St Collen in Llangollen where their memorial can be found.
Their house is now a tourist attraction run by Denbighshire County Council.
The Llangollen Historical Society, also named Hanes, is staging the special open night on 7 April at the Hand Hotel in which a film showing Llangollen at the time of World War II will be shown.
The film, which has been secured from the National Library of Wales in Aberystwyth, features an effigy of Hitler being burned at the local cattle market.
It also shows various May Day parades through the town and scenes from local agricultural shows.
The Ladies of Llangollen lived in the town for 50 years
Historical society member Idris Evans said the films would create so much local interest because they were unique.
"They provide us with a unique record of life in Llangollen as it used to be," he explained.
Money raised at the event will go towards the restoration of the Ladies of Llangollen memorial, which Mr Evans said, was popular with visitors from all over the world.
"It is a shame that it is deteriorating so much," he added.
"Their home is a museum dedicated to their lives and it is important that the memorial and tomb is preserved for future generations to enjoy."
The historical society is hoping to raise £5,000 towards the restoration.