Crossing the Black Mountains which separate western and central Bhutan, you'll enter a part of the country which until the 1970's was only reached by mule and foot trails. The mountain road passes through deciduous forests and at the second pass, Pele La (3300m), the entire area is blanketed by high altitude dwarf bamboo. About five miles from Tongsa, the road winds around a cliff and takes a sharp turn to the left. The view is one of the most beautiful sights in all Bhutan and one from which you will never tire. Sloping down the contour of a ridge stands the many-leveled Tongsa Dzong , built in 1648.