North Wales Police in the United Kingdom carried out a Misuse of Drugs Act warrant on Tuesday at a Grade I listed manor house near Caernarfon, Gwynedd, following suspicions that cannabis was being cultivated on the premises.
Officers are expected to remain at the property for several days as inquiries continue.
The sprawling mansion, boasting over 100 rooms, was once the residence of Lord Newborough and notably hosted the 1969 investiture ball for the Prince of Wales, now King Charles.
Supt Arwel Hughes revealed that a “significant grow” had been discovered but confirmed that no arrests have been made and the property owners have not yet been contacted.
Originally purchased in 2016 by a couple aiming to transform it into a luxury hotel, the building had previously seen a failed wedding venue venture in 2013.
After the luxury hotel plan collapsed, the mansion entered receivership in 2020 during a multi-million-pound renovation.
It was subsequently sold that same year and later listed for £2 million in 2024 by Manchester-based developer David Savage, though it is believed to have recently been removed from the market.
The estate, which includes eight miles of pathways, remains open to the public through Plas Glynllifon park, which on Wednesday continued to promote itself online as a place to “immerse yourself in history, culture and nature… [at] one of North Wales’s finest parks.”
Speaking about the operation, Hughes said, “We uncovered a grow, which was on the top floor of the building. We estimate around 12 rooms with grows in them and they were fairly mature plants. There’s lots of information to process today and lots of forensic work to consider, and lots of other digital matter that we are looking at. I’m quite confident we can get to a point where we can make some arrests. Clearly, the electrics are being manipulated and lots of water supply being diverted inside and the property itself is in various states of disrepair.”
He urged the public to avoid the property to ensure their safety as the investigation continues.
