English Heritage, the government's advisory body for the historic environment, has confirmed that it has taken over one of the country's largest voluntary cultural events, Heritage Open Days.

Concerns had been raised over the future of the annual event, which sees more than 3,500 historic buildings open to the public for free during September, after the Civic Trust in England entered administration in April. Among the buildings expected to open as part of this year's planned Heritage Open Days is the Churchill Archives Centre in Cambridge, which contains the personal papers of Sir Winston Churchill and nearly 600 other politicians, civil servants, military leaders and scientists.

The privately-owned Lantern Theatre in Sheffield, one of a few remaining Victorian purpose-built theatres in the country, will also be opened, while people will also have the chance to visit one of the last surviving heated lidos in Bristol. Steven Bee, English Heritage director of planning and development, said; "English Heritage can reassure all those who like to take part in Heritage Open Days that it will happen this and every year.

"Heritage Open Days is an important cultural event and we are very grateful for the continued support of all the volunteers across England, on which the success of the event depends." Heritage Open Days manager, Katja Condy, added: "We have been working very closely with English Heritage for many years, and they proved a friend when we needed them most. The transfer of Heritage Open Days to English Heritage will build on this long-established partnership."

This year's Heritage Open Days will take place between 10 and 13 September.