Bum La is an international high mountain pass at an elevation of 4.508m (14,790ft) above the sea level, located on the Indo-China border. The road to the pass has disastrous conditions and only 4wd vehicles with competent drivers are allowed.
Set high in the Himalaya mountain range, the pass links the Indian state of Arunachal Pradesh and Cona County, in the southern part of Tibet Autonomous Region in People's Republic of China. The challenging road to the summit is unpaved. Driver of the vehicle must be expert to drive on mountain terrain. As you go higher, you will be short of oxygen and your vehicle may not be your best companion to take you beyond a certain point. Take water, eatables, biscuits, chocolates if possible thermos with tea as nothing is available on the way to the summit. A special permit is required to visit the pass. The permits can be requested at the Office of the Deputy Commissioner in Tawang District, and the same has to be stamped in the Indian army cantonment of Tawang. Note that without the army stamp, you will not be allowed through the numerous check posts on the way. The pass is 108.9km (67 miles) long, running south-north from Dungkhar to Cona.
Due to heavy snow fall most of the time this place remains closed. In winter it is extremely cold. If you travel by hire vehicle make sure the driver knows the place very well and is an expert in driving specially on snow covered roads. Since the road to Bum La may not be in the best of conditions throughout the year, the ideal time to visit the place to enjoy its limitless beauty would be from May to October. The pass was the passage used by Dalai Lama to escape from Tibet and to enter India. The road to Bum La is also a historical route, the Chinese army marched into India during the 1962 Sino-Indian war. In 2006, Bum La was re-opened to traders for the first time in 44 years. Traders from both sides of the pass were permitted to enter each other’s territories, in addition to postal workers from each country.
Pic: By Tabish q - Clicked on a trip to Bumla Pass in June 2013, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=26966747