VANDALS have smashed more than 33 windows at the conservatory in Corporation Park, causing £4,000 worth of damage.
The damage, carried out with bricks, is believed to have happened on Friday night or in the early hours of Saturday.
The conservatory has been closed while the repair work is carried out and is expected to reopen by the end of the week.
Police are viewing CCTV footage to see if the yobs were caught on camera.
Council leader Colin Rigby said: "Windows have been smashed at the conservatory before but never on this scale.
"These vandals clearly spent a lot of time doing as much damage as possible. It was deliberate and pointless.
"Not only has it damaged a very much loved piece of local heritage, the repairs will cost the tax payer thousands of pounds.
"The culprits need to be caught. I would urge anyone who saw anything suspicious on Friday night to contact the police."
Anyone with information is urged to call Crimestoppers on 0800 555 111.
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