The Bhote Koshi, which runs alongside the Arniko Highway to the Tibetan border northeast of Kathmandu, is probably the steepest and hardest commercial rafting river in Nepal (Class 4+). In low water it’s like a pinball machine (and you’re the ball); in medium flows it’s more like being flushed down the U-bend of a toilet. A few companies specialize in this deviant experience, offering it as a one- or two-day trip out of Kathmandu (it’s only a three-hour drive) using road support, empty rafts and safety kayakers. At higher flows in late October and November most companies run the Upper Sun Koshi on the first day as a warm-up and the Bhote Koshi on the second day. If you have previous rafting experience or are just looking for an adrenaline rush, then this is the one for you. It’s a cold river, so if you are running it in the winter months between December and late February then look for a company that provides wetsuits and paddle jackets. An enticing option is a two-day trip, staying the night at one of the comfortable riverside resort camps.

Note that a dam is under construction near the Tibet border; when it’s complete, which may be in the lifetime of this guide, it’s likely to kill off rafting on the Bhote Koshi.