Mahendra Highway

Mahendra Highway (), also called East-West Highway () runs across the Terai geographical region of Nepal, from Mechinagar in the east to Bhim Datta in the west, cutting across the entire width of the country. It is the longest highway in Nepal and was constructed by CPWD/PWD Nepali and Indian engineers.
Overview.
The highway is mostly a single lane in each direction. It is a major infrastructure element because east–west travel was previously limited to the Hulaki Highway built during the Rana regime, expensive and limited air travel, or Nepalese trains and buses. The highway crosses the Terai from east to west for over .
The major destinations along and around the highway are Mechinagar, Bhadrapur, Itahari, Janakpur, Bharatpur, Butwal, Siddharthanagar, Nepalganj, and Bhim Dutta. Other towns on the Mahendra Highway are Birtamod, Damak, Inaruwa, Lahan, Narayangadh, Bardibas, and Chisapani
South of the highway are five official border crossing points between Nepal and India.
Infrastructure in Nepal remains neglected despite the very few "highways" that exist. The busiest highways, including Prithivi Highway, all suffer from heavy traffic.
Route (east to west).
Mechinagar (Kakarbhitta) to Hetauda.
Mechinagar, in south-eastern Nepal, is on the Nepal-India border. The wide Mechi River, a tributary of the Mahananda River, forms the border. On the Indian side, the road continues through PanitankiBagdogra and Siliguri.
From Mechinagar (Kakarvitta), the highway runs relatively smoothly for to Itahari. 
west of Mechinagar are the junctions for routes to Ilam at Charali and for Bhadrapur at Birtamod. The highway crosses innumerable streams on the way, including Khadam Nadi, east of Itahari, and Ratua Nadi, near Damak. Itahari is the road junction, with Biratnagar, on the Nepal-India border, to the south and Dharan and Dhankuta to the north.
The Koshi Barrage is from Itahari. The Mahendra Highway passes over the Barrage between Bhardaha and Bhantabari. Koshi Tappu Wildlife Reserve is easily accessible from the Mahendra Highway. The reserve office is at Kusaha off the highway.
The Mahendra Highway continues its westward course through the Terai landscape. It crosses the Balan Nadi before Janakpur junction, and another later, the Kamla Nadi river.
Janakpur, a town with more than a hundred temples, is from Biratnagar and from Birganj. Janakpur lies south of the Mahendra Highway. Hindu mythology identifies Janakpur as the capital of the ancient kingdom of Mithila.
At Pathlaiya, Mahendra Highway reaches the Tribhuvan Highway near the Indian border at Raxaul/Birganj 30 km to the south. Kathmandu is (by highway) north of this junction. The two highways join to cross the Siwalik Range to Hetauda in Chitwan Valley. At Hetauda's Buddha Chok the two highways diverge and the Mahendra Highway heads west.
Hetauda to Bhim Datta.
Bharatpur is the much-used junction for the highway to Mugling on the Prithvi Highway. It is also the endpoint of many rafting trips on the Trishuli River, after it joins the Narayani River at Devghat. The Mahendra Highway runs north of Chitwan National Park .
Butwal is the junction of the Mahendra Highway with the Siddhartha Highway, with Lumbini, the birthplace of Gautama Buddha (Nepal), Sunauli, Maharajganj, on the Nepal-India border, and Siddharthanagar to the south and Tansen and Pokhara to the north. Passes through Nawalparasi district. Butwal is on the west bank of the Tilottama River in the shadow of the Churia Hills.
West of Butwal, the highway turns north to cross the Dudhwa Hills (350m ascent) into Inner-Terai Deukhuri Valley, then crosses the West Rapti River, which is no relation to the East Rapti River of Chitwan. Just beyond the river (291 km from Hetauda), the highway reaches Bhalubang, where a spur road continues north into Pyuthan and Rolpa districts. The Mahendra Highway heads west again, following the Rapti downstream through Deukhuri. 27 km west of Bhalubang at Lamahi, a spur road goes north to Dang Valley, Dang Airport, and Tulsipur town. 35 km beyond Lamahi, Rapti Highway departs north for Salyan and Rukum districts.
Kohalpur, 428 km west of Hetauda, is the junction for highway south to Nepalganj and the border with India and north to Birendranagar in Surkhet. Then the highway passes the Kusum-Ilaka forest, which is being eyed as a potential extension area of Bardia National Park, which lies to the north-west of Nepalganj, on the Nepal-India border.
Crossing the Karnali River at Chisapani, the highway continues west to the Indian border at Bhim Datta on the Mahakali River, crossing on a barrage. The section between Chisapani and Bhim Datta is in poor repair. There is a extension to Banbasa, the first town in Uttarakhand, India.
Major junctions.
The major junctions of Mahendra Highway are: