Atal Marg (Manali-Leh Highway)

Atal Marg (the Manali-Leh Highway, also designated NH-3) is a 428 km strategic highway from Manali (Himachal Pradesh) to Leh (Ladakh) — connecting the Indian plains to one of the most strategic high-altitude border regions of India. The route crosses 5 high-altitude passes: Rohtang La (3,978 m, now bypassed by Atal Tunnel), Baralacha La (4,890 m), Lachung La (5,059 m), Nakee La (4,770 m), and Tanglang La (5,328 m — the world's second-highest motorable pass).

The highway is operational only ~6 months per year (May/June to October/November) due to the extreme winter — heavy snowfall closes Baralacha La, Tanglang La, and other high passes from November to May. The Atal Tunnel (operational 2020) bypasses the Rohtang La closure and provides year-round access to Lahaul valley up to ~80 km of the alignment, but the rest remains seasonal.

Maintained by Border Roads Organisation (BRO) since the 1960s, the highway is critical for Indian Army supply to Ladakh's forward border positions adjacent to the disputed Sino-Indian border in eastern Ladakh. During summer, BRO operates a continuous troop convoy + supply movement system using the highway as the primary north-south military supply route.

In 2020, the Government of India officially renamed the highway 'Atal Marg' after Atal Bihari Vajpayee, the BJP Prime Minister whose government sanctioned the Atal Tunnel that complements the highway.