A balls deep look into the unbelievable tailrace tunnel behind the thundering falls of Niagara. 2 brits and 1 australian team up to abseil into this abandoned 9m tall, 100 year old brick tunnel. Grab a drink and get comfy, this is top shelf.

On my first trip to Paris I arrived into Gare du Nord and entered the dense maze that is the metro. Despite the crowds, the noise and the distinct odour of piss, I was in love. The kind of love which inspires one to risk life, limb and deportation to get up close and personal.

Visible from from the city limits with its taunting gaze and mocking laugh, we knew deep down we could not resist. For months wed watched and waited noting the slow progress skywards. All the notches on our well-worn belts faded before this opportunity.

qx and I sat upon a rusty gate staring vacantly down a rough asphalt road that veered not an inch far as the eye could see. It split the swamps neatly in two under a cloudy winter sky. Into the distance rotting power poles line the road, like a dead army of withered old men waiting for a good break in traffic. A chill wind spurred us to action and we dropped from the gate and began the hike.

Wildeyed and hyperventilating, you turn terrified to face the lights racing down the tunnel. Thundering towards you swaying side to side like a loping predator, eyes blazing, comes a London Underground train.

Probing the edges of system late one night we found her, The One. That place in the system which sets itself apart from the rest. Like NYC's City Hall or Sydney's St James, this is Paris' jewel. An abandoned tunnel packed with the fading red and green of vintage Sprague rolling stock.