Bletchley Park is closing for three days in November due to filming.
The site in Milton Keynes will be closed from Wednesday, November 17 to Friday, November 19 to all members of public.
Bletchley Park is a heritage site and museum - it became the principal centre of Allied code-breaking during the Second World War.
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Members of the public shared their excitement of the news speculating the filming could be regarding The Rose Code - a novel about the female code breakers at Bletchley Park.
Bletchley Park stated on their Facebook page: "I’m afraid we aren’t able to release any details regarding the filming at this time."
Any organised or pre-booked days out and school trips have been cancelled for the filming.
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On their website, Bletchley Park said: "Due to the financial impact of COVID-19 on the Trust, the decision to close has been an economic one. The closure is not being undertaken without considerable thought, but the filming presents the Trust with an unprecedented commercial opportunity.
"We apologise for the inconvenience this will cause those who have booked to visit. We will be in touch directly to rearrange your booking. If you were planning on visiting us, we hope to see you on an alternative date.
"Thank you, in advance, for your understanding and your support."
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