Avoncroft Museum in Worcestershire has had to close after it was vandalised on Saturday evening (May 1).
The museum opened on Saturday for the first time since last October.
However, it had to close on the second day after employees came in to find windows smashed.
The museum posted a message on Twitter saying it had to close today due to safety concerns after many of the windows on site had been smashed.
Employees say they feel "devastated" after spending weeks with volunteers to prepare the site for reopening.
The museum has been vandalised in the past but this has been described as one of the most serious vandal attacks it's had.
The Avoncroft Museum is England's first open air museum. It has over 30 historic Midlands buildings that were rescued from the threat of demolition.
Volunteer, Nick Sturgess, has been deeply angered by the attack and has described it as "malicious and pointless".
The museum are now appealing for donations to help repair the damage.
Watch Yasmin Bodalbhai's full report: