Emergency services rushed to the former Broadmoor Psychiatric Hospital after a fire broke out.
Dozens of firefighters were seen at the site, with crews arriving at around 9:30am on Saturday, May 25.
This included crews from Crowthorne, Bracknell, Ascot, Wokingham, Wokingham Road, Whitley Wood, Caversham Road and Slough - totalling approximately 40 firefighters.
No injuries were reported, although the fire was described as "well-developed".
The site of the hospital, in Chaplain's Hill, Crowthorne, has been derelict for years - so no staff or patients were at risk.
However, members of the public were told to avoid the area and keep their doors and windows closed.
As of 3pm, the fire has been brought under control.
Videos from the scene have since emerged, showing flames and smoke coming from the rear of the building.
Broadmoor on fire Massive blaze engulfs psychiatric hospital(UK) 2505024
— john l (@Maeestro) May 25, 2024
A huge blaze has broken out at a derelict building on the old Broadmoor Hospital site.Crews from Royal Berkshire Fire and Rescue service are in attendance at the site. pic.twitter.com/EPXiuTGWpD
Broadmoor was built in 1863 as the country's first asylum for the criminally insane.
It went on to house notorious criminals including gangster Ronnie Kray and serial killer Peter Sutcliffe.
The site closed in 2019 and has remained vacant for five years, with patients and staffed moved over to the new Broadmoor Hospital, which detains men under the Mental Health Act.
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