I am suspended from a wire at 1800 feet, and looking down at what was until the 1950s the largest man-made hole on the planet. And I’m about to travel at a speed of about 75mph.

I am at Zip World, and this is the northern hemisphere’s longest zip wire. At one mile in length – and after several weeks’ uncertainty thanks to the wintry weather conditions – it is finally open for business. I started my journey in the base of Penrhyn slate quarry, which the wire travels over. Once the largest slate mine in the world, it still employs around 300 people, producing some of the finest slate on earth.

But once it employed some 4000 and for decades the question of how to regenerate the local economy has gone unanswered. Until now, that is. Zip World owner Sean Taylor, had his “eureka moment” in 2010. In the area to watch rugby he visited the quarry and had one simple thought: wouldn’t this be a great place for a zip wire? Three years later and his dream has finally been realised, employing plenty of local people in the process.

Every five minutes two people will travel down parallel wires for a mile – and I am going to be one of the first. I am told to assume a push-up position on the launch platform and am clipped on to the wire above me. My harness takes the strain and I am suspended. “Safetys off” and I am ready to go. Three, two, one… and I am flying. This is the closest you will get to sky diving without jumping out of a plane and it is incredible. The ground rushes beneath me, at times just metres away, and suddenly I am over the lake in the quarry’s base. It is quite astoundingly blue – like a pool of fountain pen ink – and I become lost in it. Time slows down, I seem to slow down, and I take it all in. The North Wales coastline just ahead, the Isle of Man beyond, the mountains of Snowdonia to my right. It is spectacularly beautiful.

But don’t take my word for it. Get up here and try it for yourself, or click here to watch our video. Zip World (01690 710914) is open daily and costs £50 for adults and £40 for children under 16. A family ticket for two adults and two children costs £160. The experience lasts about two and a half hours, including the little zipper and big zipper wire rides and a commentary about the slate quarry’s history.