An exhibition about the Cottingley Fairies hoax will be held when scores of historic properties throw open their doors to the public next month.

Visitors will be able to see a display about the Cottingley Fairies at Cottingley Town Hall, where Frances Griffiths and Elsie Wright attended school.

During the First World War, the cousins caused an international sensation by using hat pins and cut-out paper fairies to create staged photographs apparently proving the existence of fairies.

Their story, later revealed as a fake, will be told in an exhibition of photographs, and publications as part of a Heritage Open Day events across West Yorkshire.

A Victorian mansion owned by an anti-slavery campaigner is also among scores of historic properties in Bradford district throwing open their doors to the public. Visitors will be able to visit Heaton Mount, now home to Bradford University School of Management.

There will be a guided tour of the building owned by abolitionist and textile magnate Fred Ambler, in A Tale of Two Buildings. The Neo-Gothic building, off Emm Lane, was built in 1874.

Helen Keighley, outreach manager for English Heritage, said: “Every year the event gets bigger. Many of the properties opening up are normally off-limits to the public, so this is a fabulous opportunity to explore, discover and have fun.”

The open days will include the 1880s Bradford Reform Synagogue in Bowland Street, Manningham, which is one of the oldest Reform Synagogues outside London.

Bradford Tradesmens’ Homes in Heaton Road, will also open to the public and visitors to Lister Park will have the rare chance to look out from the balcony at Cartwright Hall.

Visitors to Otley Chevin Forest Park will be able to trawl through its history, including its rocky ridge which inspired artist William Turner to paint Hannibal over the Alps.

They will also be able to go behind the scenes at Cliffe Castle Museum, Keighley, or visit Farfield Quaker Meeting House in Addingham, which was built soon after the religious turmoil of the English Civil War.

Other historic homes and museums in Bradford, Keighley, Ilkley, and Rawdon will also be taking part. Nationally more than one million visitors are expected to explore more than 4,000 buildings and events from September 9 to 12. For more information, visit heritageopendays.org.uk