At the end of the corridor there’s a short flight of stairs into the main saloon bar. That’s where the actual chestnut tree that presumably gave the pub its name grows out of the wall behind the bar. Or rather doesn’t grow, because it’s been dead for more than a hundred years, but its branches spread out in a tangle of bare limbs across the width of the saloon where they merge with the wooden booths that lurk in the gloom on the other side. Amongst the branches hung dusty iron and glass lamps holding what I really hoped were fake gas mantles, because using real ones would have been a bit of a health and safety violation.

As I walked in, I caught a whiff of old sweat and hot pie which might have been bad ventilation or the memory of the crowds that flocked to this end of the Tyburn Road to watch the felons morris at the end of the rope.

Morris being an old word for dance, by the way – it’s amazing what you pick up on the job.

The woman behind the bar was reassuringly Romanian and didn’t flinch when I showed her my warrant card and asked to see the manager. The barmaid explained that she was out getting her lunch, but was expected back any minute. In the meantime would we like a drink?

Not being tied to a brewery chain, The Chestnut Tree offered a range of beers in the mid- to totally obscure CAMRA range. I had a half of Sambrook’s Junction Ale, just to keep everything friendly and relaxed you understand, and Guleed had an orange juice and Perrier.

It wasn’t easy, but we managed to find a table from which we could keep an eye on most of the saloon bar. The table top was made from planks of wood that had grown pitted with use and warped with age, possibly before being lacquered with what looked like about half a centimetre of varnish. Despite the ancient beer rings worn into the surface there was a printed sign in a freestanding iron frame which requested patrons to preserve the natural beauty of the genuine antique furniture, thank you – the management. In front of this was a stack of mismatched beermats. When I had a flick through, I found they were all from different breweries and, where marked, from different pubs. I learnt much later that it was considered good form for patrons to nick beermats from other pubs and donate them to The Chestnut Tree. The really rare ones from places like Tibet or obscure bars in Abeokuta ended up pinned to a cork board behind the stage in the adjoining public bar.

‘They have live music here,’ said Guleed, who’d found a leaflet stuffed into the iron frame. ‘Someone called the “Shanren Mountain Men Band” tonight – ever heard of them?’