Sankhuwasabha Districtसङ्खुवासभा जिल्ला

Sankhuwasabha is the largest district in Koshi Province at 3,480 km², running from subtropical valleys around 457 m all the way to the summit of Makalu, the world's fifth-highest mountain (8,485 m on the modern survey; older maps print 8,463 m). The Arun river, descending from Tibet, has cut one of the deepest valleys on Earth through the district's middle. Its upper reaches lie inside Makalu Barun National Park, established in 1992 across 1,500 km² of Sankhuwasabha and Solukhumbu (with an 830 km² buffer zone) — the only protected area in the world spanning more than 8,000 m of vertical relief.

The Arun's power has also made Sankhuwasabha the stage for one of Nepal's longest-running development sagas. The original World Bank-backed Arun III hydropower scheme collapsed in 1995 when the Bank withdrew under environmental and economic criticism — a landmark episode in Nepali development politics — before being revived under a 2014 agreement with India's SJVN, which began building the 900 MW run-of-river project in 2018; Nepal is to receive 21.9% of its electricity free during the 30-year concession.

The district headquarters is Khandbari, the largest of five municipalities that sit alongside five rural municipalities including Makalu and Bhotkhola in the high north. The people are an eastern-hill blend — Rai (17.3%), Chhetri (11.3%), Tamang (8.9%) and the indigenous Kulung (6.7%) — split religiously between Hinduism (40.4%), Kirat (28.8%) and Buddhism (26.7%). Its 2021 population of 158,041 was essentially flat against 2011, and with a sex ratio of 101.42 it is one of only three Koshi districts with more men than women.