Birgunj (also Birganj) (Nepali: बीरगंज) is a metropolitan municipality and border town in Parsa District in the Narayani Zone of southern Nepal. It lies 283 km (176 mi) south of the capital Kathmandu, attached to north of the border of the Indian state of Bihar. As an entry point to Nepal from Patna and Kolkata, it is known as the "gateway to Nepal". The town has significant economic importance for Nepal as most of its trade with India is via Birgunj and the Indian town of Raxaul. Tribhuvan Highway links Birgunj to Nepal's capital, Kathmandu.
Birgunj was established as a conglomerate of several villages in and around Gahawa Mai Temple. Gahawai Mai Temple remains the epicenter of the town. The settlement was named after the Rana Prime Minister Bir Shamsher, thus acquiring the name Birgunj .
According to the 2011 Census, Birgunj had a population of 139,068. It is the biggest city in Narayani Zone and the headquarters of Parsa District.Bhojpuri language is the main language spoken. In addition to Nepali, several other languages are spoken, including Bhojpuri, Maithili and English. Nepali is the official language. Bhojpuri language is the native language.