I'm in one of the many clandestine Amsterdam-style coffee shops to have popped up across the UK over the past few years – places that all have their own motivations and character, whether they're open-doored and profit-driven or more private and community-based, but which all share one key characteristic: you can smoke – and sometimes buy – weed on the premises. This is just one of six venues that I know of in this part of London, and beyond the capital similar set-ups exist all the way from Peterborough to Newcastle.

Sitting six floors up, looking down on London's rooftops and the City workers leaving the high rises nearby, I sip a coffee and puff a joint of Moroccan hash, bought over the counter five minutes ago.

These under-the-radar smoking spots have been around for years – famously, cannabis legalisation campaigner Colin Davies was arrested in 2001 after opening The Dutch Experience cafe in Stockport, Greater Manchester – but there's evidence that there's been a jump in numbers recently. Granted, that evidence is entirely anecdotal, but considering these places aren't exactly going to be clamouring to register with their local councils, it's about the best kind of evidence we have.

The address of the venue itself isn't publicly available, but like many other UK cannabis clubs the Teesside branch maintains a website and Facebook page, with Michael's face up there for everyone to see. Being such a public venture, what do the locals make of it, and is there not a worry that police are going to come charging through the door at any point?

"We currently have just under 100 members, but we have new people contacting us every month," says Michael Fisher, cannabis activist and founder of the club. "Some people come from up to 50 miles to come here and spend an evening." Attendees range from 20 to 70 years old, he says, and some of the "older members are actually starting to bring their friends".

The Teesside Cannabis Club – a local chapter of the UK Cannabis Social Clubs – has been operating as a hub for the local weed-smoking community for many years, but early in 2017 members decided to find and open a permanent venue for social cannabis consumption. Unlike some of the more low-key set-ups, absolutely nothing illegal is sold here. The club provides the coffee shop experience, selling soft drinks and snacks, but has a strict bring-your-own policy when it comes to the cannabis itself. There's also a ban on any alcohol and hard drugs.

"We really get on with the locals – we chat to everyone, we don't cause problems," says Michael, highlighting the fact that getting on with the locals has meant no one's reported them, which means a lack of police attention. "It's probably the world's worst kept secret where we are, and we just bought a new 6ft sign to put up outside. The police don't need to raid the club – they can see everything we do on social media, and if there are any problems they have my mobile number; they know where I live."

The Teesside club falls under the jurisdiction of Durham Police Force – the first in the UK to publicly relax its stance on cannabis policing, with Commissioner Ron Hogg saying in 2015 that users will only be targeted if they're growing plants for commercial gain or smoking weed in a "blatant" way. The fact that all consumption takes place behind closed doors undoubtedly acts in the Teesside club's favour, but perhaps its main saving grace is its strict no-drugs-for-sale policy.

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Other coffee shops – i.e, the ones that sell cannabis products over the counter – don't have this kind of luxury; if the police were aware of them, they would likely swoop in to close them down. However, these places also provide something you won't find anywhere else in the UK: a menu to choose from, and time to inspect the product before buying, without the pressure and potential rip-off of a rushed street corner deal.