A five-minute walk from a parking spot at a bend in the road leads to a picturesque pool in a shadowy ravine of the Tang Chhu that is known as Membartsho (Burning Lake). The 27-year-old Pema Lingpa found several of Guru Rinpoche's terma here. It's a lovely, if slightly unsettling, spot, where nature, religion and mythology blur into one.

A wooden bridge crosses the prayer-flag-strewn gorge and offers a good vantage point over the 'lake'. Only the enlightened will spot the temple that lurks in the inky depths. The sanctity of the site is made evident by the numerous small clay offerings called tsha-tsha piled up in various rock niches.

Under a rock shrine with a carving of Guru Rinpoche flanked by Sakyamuni and Pema Lingpa is a cave that virtuous people can crawl through, no matter how big they are. Beware: it's quite small, and very dusty. Also, don't venture too close to the edges of the ravine for that elusive photo angle. Vegetation hides where the rock ends and a treacherous drop into the river begins. Sadly there have been several drownings in the swift waters here.