Udayapur Districtउदयपुर जिल्ला

Udayapur is an inner-Tarai (bhitri madhesh) district of 2,063 km² folded between the Mahabharat range, which covers about 60% of its area, and the Chure hills, with valley floors from about 360 m rising to 2,310 m. Forest blankets some 67% of the district. The headquarters Gaighat lies in Triyuga Municipality, the most populous of four municipalities that sit alongside four rural municipalities; the western tip of the Koshi Tappu Wildlife Reserve, Nepal's first Ramsar site, extends into the district's southeastern corner.

Udayapur hosts one of Nepal's flagship state industries: Udayapur Cement Industries at Jaljale, established on 14 June 1987, built by a Japanese consortium (Onoda Engineering design; Kawasaki Heavy Industries and Tomen construction), feeding on local limestone delivered by a 13.8 km ropeway and selling under the 'Gaida' brand — one of the few government-owned factories in Nepal to have accumulated profits. Together with farming in the Triyuga and Tawa valleys, the plant makes Udayapur one of only four Koshi districts whose population grew between 2011 and 2021 (+0.68% a year, to 340,721).

The district's history reaches back to the eastern Sen kingdoms: the hill fort of Chaudandigadhi — now the name of a municipality — fell to the Gorkha army on 16 July 1773 during Nepal's unification campaign. Today's population is led by hill Janajati communities (about 44% combined, with Rai the largest group, followed by Magar and Tamang), and the sacred pond and Mahadev temple at Rauta, in Rautamai Rural Municipality, is the district's best-known pilgrimage site.

Before the unification of modern Nepal in the late eighteenth century, the area of present-day Udayapur lay within the eastern Sen kingdom of Chaudandi, one of the successor states that broke away from the older Makwanpur Sen realm. The kingdom's seat was the hill fort of Chaudandigadhi, whose ruined ramparts still crown a ridge above the lowlands. The expanding Gorkhali (Shah) army captured Chaudandigadhi on 16 July 1773 during Nepal's unification campaign; the last Chaudandi king, Karna Sen, fled eastward to Bijayapur (near present-day Dharan), and the territory was absorbed into the kingdom of Nepal.

The district takes its name from Udayapurgadhi, another old hill fort that long served as the centre of the area. Udayapurgadhi stands at roughly 1,300 metres above sea level and commands sweeping views over the surrounding hills and, to the south, the Tarai plains. As roads and population shifted toward the valley floor, the headquarters function moved off the ridge: the district was administered from Panchawati until 1972, when the headquarters was relocated to Gaighat in the Triyuga valley, where it remains today.

In the modern era Udayapur became a centre of Nepal's state-led industrial planning, anchored by the government-owned Udayapur Cement Industries, established at Jaljale on 14 June 1987. Following the 2015 constitution and the 2017 restructuring of local government, the district was reorganised into eight local levels — four municipalities (Triyuga, Katari, Chaudandigadhi and Belaka) and four rural municipalities (Udayapurgadhi, Rautamai, Tapli and Limchungbung) — within what is now Koshi Province. The municipalities of Chaudandigadhi and Udayapurgadhi preserve in their names the two historic forts at the root of the district's story.

Udayapur is an inner-Tarai (bhitri madhesh) district of about 2,063 km², set between two parallel hill ranges: the higher Mahabharat (Lesser Himalaya) range to the north, which covers roughly 60% of the district, and the lower Chure (Siwalik) hills to the south, covering about 9%. Where the two ranges converge in the west they enclose the Udayapur Valley, the inner-Tarai basin that gives the district its character. This inner-Tarai belt makes up about 31% of the land and lies between roughly 360 and 550 metres, while the district as a whole ranges from about 360 metres on the valley floors up to 2,310 metres on the Mahabharat ridgelines.

The valley is drained by the Triyuga river, the district's largest, which runs eastward through a wide basin before joining the Koshi. The Tawa Khola and the Vaidyanath (Baidyanath) are other important streams, while the great Sapta Koshi forms the district's eastern border and the Sun Koshi marks part of the north. The headquarters town of Gaighat and other settlements lie in the inner-Tarai zone along the Triyuga and Tawa.

Forest blankets a large share of the district — roughly two-thirds of the land area is wooded — giving Udayapur extensive subtropical sal forests on the lower slopes. The climate is shaped by elevation: lower- and upper-tropical zones (below about 1,000 m) account for most of the district, with a subtropical belt on the higher hills and only a sliver of temperate climate on the highest ground. The far southeastern corner of the district touches the floodplain of the Koshi Tappu Wildlife Reserve, Nepal's first Ramsar wetland.

Udayapur's economy combines subsistence hill and valley farming with one of Nepal's flagship state industries. Agriculture remains the backbone for most households: rice, maize, wheat and millet are the staple cereals grown across the terraced hills and the alluvial floors of the Triyuga and Tawa valleys. Maize is especially important, and the fertile valley belts around Triyuga, Belaka, Katari and Chaudandigadhi have increasingly turned to commercial vegetable cultivation, including cauliflower, cabbage, tomato, potato, radish and chillies, as a route to cash income.

The district's industrial anchor is Udayapur Cement Industries Limited at Jaljale, established on 14 June 1987 and owned by the Government of Nepal. The plant sells cement under the 'Gaida' brand and is one of the few state-owned enterprises in Nepal to have run at a cumulative profit. It draws on high-grade limestone mined in the nearby Sindhali hills, delivered to the factory by a long bicable ropeway; its capacity grew from an initial 800 tonnes per day to 900 tonnes per day after a 2019 upgrade, and the limestone reserves are projected to last on the order of two centuries.

Improving connectivity is reshaping the local economy. Gaighat lies on the Sagarmatha (Koshi) Highway corridor, and the north–south Koshi Corridor road — running from Sunsari across the Koshi bridge at Chatara and on through Udayapur toward the hills of Khotang — has lifted trade, transport and market access for the district. Partly because of this mix of industry, farming and improving roads, Udayapur was one of the few districts in Koshi Province whose population grew between the 2011 and 2021 censuses rather than declining through out-migration.

Udayapur is a meeting ground of hill and Tarai peoples, and hill Janajati (indigenous) communities together form the single largest grouping, about 44% of the population. The Rai are among the most numerous communities, alongside Chhetri, Magar, Tharu and Tamang, with Kami, Bahun and Newar also well represented — a diversity that reflects the district's position where the eastern hills descend into the inner Tarai.

This mix is mirrored in language and religion. Nepali is the mother tongue of about half the district, while Magar (Dhut), Tharu, Chamling, Tamang, Maithili and Bantawa are all widely spoken first languages. Hinduism is the majority faith at roughly 70%, but the Kirat Mundhum religion of the Rai and Limbu communities (around 13%) and Buddhism (around 12%) give the district a distinctly plural religious landscape, with smaller Christian, animist (Prakriti) and Muslim minorities.

Festivals follow this cultural blend. The Rai community's Sakela (Sakewa) dances mark the agricultural year, Hindu festivals such as Dashain, Tihar and Maghe Sankranti are widely observed, and the Triveni (Tribeni) fair at a river confluence near Katari draws crowds of pilgrims around Makar Sankranti each January.