With no days left on our Thai visa we crossed the border at Chiang Khong, north of Chiang Mai and took a small boat over Mekong into Laos. We landed in the border town of Houay Xai. There's not really much to Houay Xai and travellers generally just jump straight on to a boat bound for Luang Prabang. But we hung around because the one thing Houay Xai does have is The Gibbon Experience.

To be honest, I wasn't going to say too much about the Gibbon Experience on here at first. Not because it was boring or anything, rather because I didn't think I could do it justice. But then Si said that I was copping out and that I should just use my "flowery words". So - if you're ready - here is my attempt at describing the Gibbon Experience...

Imagine hanging in the air between jungle-clad hillsides and looking out over an isolated valley winding it's way towards distant blue mountains, crowned by billowing white thunderclouds. Imagine looking down beyond your freely swinging feet and seeing forest giants turned to matchsticks 100m below. Now imagine that you are seeing this as you whizz along a zipwire at 50 kph, dangling in your harness with only a piece of tyre rubber to slow you down. Seconds feel like hours as the speed, sights and sounds are burned into your braincells forever and you can't stop yourself from whooping as you go, because you have to let the awesome out somehow! Imagine doing this not once, but again and again, covering the jungle in these half-kilometre stretches of exhilaration, all day long.

Now see yourself in a fairytale treehouse whose only walls are a forested infinity of hills. Eat freshly made local food until you're bursting and toast the day with your new friends until you can't stay awake any more; then allow yourself to be lulled to sleep by the sound of the rain falling in the jungle below you. Wake up the next day, rub your eyes, and then do it all over again.

It's better than scrambling in Snowdonia, better than climbing in Font, better than via ferrata in Italy and better than every roller-coaster or water slide I've ever been on all added up and multiplied by a hundred. I've thought about it carefully and I can honestly say that the Gibbon Experience is the coolest activity I have ever done in my entire life, ever.

And we didn't even see gibbons.