National Highway 1 in India runs between the union territories of Jammu & Kashmir and Ladakh. It comprises parts of old NH1A and NH1D. The number 1 indicates, under the new numbering system, that it is the northernmost East-West highway in India.

Ladakh is a region administered by India as a union territory and constitutes an eastern portion of the larger Kashmir region that has been the subject of a dispute between India and Pakistan since 1947 and India and China since 1959. Ladakh is bordered by the Tibet Autonomous Region to the east, the Indian state of Himachal Pradesh to the south, both the Indian-administered union territory of Jammu and Kashmir and the Pakistan-administered Gilgit-Baltistan to the west, and the southwest corner of Xinjiang across the Karakoram Pass in the far north. It extends from the Siachen Glacier in the Karakoram range to the north to the main Great Himalayas to the south. The eastern end, consisting of the uninhabited Aksai Chin plains, is claimed by the Indian Government as part of Ladakh, but has been under Chinese control.