well maintained (except in a few places where washouts or falling rock occur). Hired vehicles (two and four-wheel-drive), heavy trucks, and motorcycles regularly travel into the Nubra Valley, though special permits are required to be arranged for travellers. The elevation measure from hundreds of GPS surveys matches SRTM data, ASTER GDEM data, and Russian topographic mapping. It is broadly consistent with numerous GPS reports. The nearest sizable town is Leh. Leh is connected by road from Manali and Srinagar, and daily flights are operated from Delhi. From Leh, a daily bus service to Nubra Valley passes over Khardung La which may also be reached by a hired car with an experienced driver or by motorcycle. The two bases on either side of Khardung La are North Pullu and South Pullu. An Inner Line Permit (ILP), which can be acquired at the District Commissioner's office in Leh, is required for tourists (not needed for Ladakh citizens). People are required to check in en route and must provide photocopies of the permits to be deposited at each checkpoint. Altitude sickness is a serious health concern for people not acclimatised to high altitudes. Prophylactic altitude-sickness medication such as acetazolamide may be necessary for some as there are no emergency medical facilities to treat altitude sickness along the route. The road is closed from approximately October to May due to snow and is often subject to long delays due to traffic congestion on narrow one-lane sections, washouts, landslides and road accidents. Climate Khardung La has an arctic tundra climate (ET) with short, cool summers and long, very cold winters. Gallery See also Silk Road Extreme points of Earth Umling La References Mountain passes of Ladakh Mountain passes of the Himalayas Tourism in Ladakh