UK Crime Gangs Turn Historic Castles and Luxury Mansions Into Huge Cannabis Farms

Britain’s picturesque countryside, known for its grand estates, historic castles and sprawling farmland, is becoming the setting for a disturbing criminal trend. Organized crime groups are increasingly transforming stately homes into large-scale cannabis farms, using the isolation and size of these properties to conceal illegal operations worth millions of pounds. Experts say the reality resembles the fictional crime world of Netflix’s The Gentlemen—but behind the impressive architecture lies a far more troubling picture involving exploitation, dangerous working conditions and serious public safety risks.

According to a report by The Sun, criminal networks are moving beyond the smaller growing operations traditionally found in residential properties and establishing industrial-scale facilities in remote mansions and rural buildings. In the year ending March 2025, police and Border Force recorded 10,689 seizures involving cannabis plants across the UK, a 10% increase from the previous year. Drug expert Ian Hamilton, an associate professor at the University of York, told the newspaper that larger rural properties allow criminals to increase production while making their activities harder to detect.

One striking example emerged in April 2026, when police raided Plas Glynllifon, a historic mansion near Caernarfon in North Wales. The Grade I-listed property, which contains more than 100 rooms and once hosted a celebration connected to the investiture of the Prince of Wales in 1969, was found to contain cannabis crops across 12 rooms. Investigators discovered equipment used to support the operation, including artificial lighting powered by unsafe electrical arrangements and a diverted water supply. The scale of the discovery highlighted how even historically significant buildings can be repurposed for organized criminal activity.

Another major operation was uncovered at Woodlands Castle near Taunton, Somerset. The former wedding venue, set on approximately 12 acres, was found to contain around 3,500 cannabis plants in 2021, with a potential value estimated at £1.4 million. Almost every room had reportedly been adapted for cultivation, with specialized lighting and growing equipment installed throughout the property. Trung Pham, who claimed he had been kidnapped and forced to work at the site, was later convicted of involvement in cannabis production and sentenced to three years in prison.

The problem extends beyond the illegal production of drugs. Experts warn that vulnerable people, including migrants and young adults, can be recruited, manipulated or forced to work in these operations under exploitative conditions. Some workers are reportedly made to live in poor surroundings while maintaining the growing facilities. Hamilton said people who are socially isolated or experiencing personal difficulties can be particularly vulnerable to being drawn into criminal networks. These cases raise wider concerns about human trafficking and the exploitation of people who may have limited options for seeking help.

Remote properties offer criminal groups several advantages: fewer passersby, greater control over access and enough space to produce large quantities of cannabis in one location. However, these operations can also create serious hazards. Unsafe wiring, overloaded electrical circuits and the combination of electricity and water in humid growing environments can lead to fires. According to figures cited by The Sun, the Home Office recorded 640 fires linked to cannabis farms across the UK between 2019 and 2024, while South Wales Fire and Rescue Service attended 90 suspected or identified cannabis-farm properties over seven years.

Authorities and experts now face the challenge of identifying these increasingly sophisticated operations before they cause further harm. The discovery of illegal farms inside prestigious country houses demonstrates that criminal activity is not confined to urban neighborhoods or abandoned industrial buildings. Behind the imposing gates and historic façades, these properties can conceal extensive networks that exploit vulnerable workers and pose risks to surrounding communities.

Source: The Sun