As with Parkour, buildering in London is often more accessible, draws less attention, and often reveals some interesting architecture when you head out of the city centre and into the housing estates. Parts of residential London are incredibly densely packed, and John is proving a dab hand at stumbling upon some real nuggets. He'd discovered an estate in the south of the capital whilst out on one of his nocturnal running missions and suggested that we head there to see what else we could find.

On his jogging reccy visit, John had spotted a disused, elevated playground. These are another curious feature of London's housing estates - random communal play areas scattered amongst post war edifices that have fallen into disrepair. Like many others, this one had become the domain of taggers, smack addicts and glue sniffers, and as a result, it was no longer accessible. A rusty gate and a wall topped with swiveling spikes meant that we had to clamber over a ten foot pronged railing, but it was well worth the effort.

As you will notice, the wonderful red brick of the buildings isn't coped as fully as modern walls, giving plenty of opportunity for some very fingery problems. As we discovered later on, the estate is actually listed, meaning that it is protected due to its status within the architectural and cultural history of the area. We had just started to wander up the road to another housing estate when we spotted two low buildings with an alley running in between. It was begging to be chimneyed - not a tricky ascent but quite satisfying, especially given the height.

"She assured us that she didn't mind in the slightest but asked us, half-jokingly, if we would mind removing the rubbish that had collected on the flat roof."

As John joined me on the roof, a resident leant over her balcony and asked us what we were doing. Initially we figured we'd upset her - we were climbing right next to her flat and at a glance, it could easily be regarded as suspicious, potentially damaging, and reckless. I immediately apologised and told her that we would be moving on very shortly. She assured us that she didn't mind in the slightest but asked us, half-jokingly, if we would mind removing the rubbish that had collected on the flat roof. We happily obliged and she passed down some carrier bags into which we placed a shoe, some syringe needles, various cans and bottles and a coat hanger. We're such nice young men.

Our final stop of the day was about a mile up the road: a small housing estate with a concrete communal area, dotted with flowerbeds and a low building that offered a nice wall-run to muscle up - a nice combination of parkour and climbing. Not the most visually striking, but I grabbed a quick shot of John as it's a movement that he really enjoys doing.

A great day's climbing, and my thanks to John for showing me the new spot. I'm hoping to return the favour in the next couple of weeks, and I'll be sure to take my camera along again.