Explanation:

A major part of NH 7 covers the North-South Corridor of NHDP and it is officially listed as running over 2,369 km (1,472 mi) from Varanasi to Kanyakumari. It is the longest “Single” national highway in India. In case of NH 44, which is considered to be the North-South Corridor of NHDP (National Highway Development Project). It has come into being by merging seven previously differently numbered national highways in full or part starting from former NH 1A from Srinagar (J&K), former NH 1 in Punjab and Haryana ending at Delhi, part of former NH2 starting from Delhi and ending at Agra, former NH3 (popularly known as Agra-Bombay highway) from Agra to Gwalior, former NH 75 and former NH 26 to Jhansi, and finally former NH 7 via Nagpur, and Adilabad, Nizambad, Hyderabad and Kurnool, and Bangalore,Dharmapuri, Salem, Tirunelvi and Madurai terminating at Kanyakumari.