Nawalparasi West Districtनवलपरासी (बर्दघाट सुस्ता पश्चिम) जिल्ला

Nawalparasi West — officially "Nawalparasi (Bardaghat Susta West)", and "Parasi" in NSO tables — is one of Nepal's two newest districts, created when the 2017 federal restructuring split old Nawalparasi between Lumbini and Gandaki provinces. Its statistical area of 729 km² is the third-smallest in the country, a Tarai strip between Rupandehi and the Narayani (Gandak) river, which swings along its southeastern edge to the Gandak barrage on the Indian border; the Susta pocket on the river's far bank, administered as Susta Rural Municipality, is the best-known unresolved segment of the Nepal–India boundary. The 2021 census counted 386,868 people, up 1.47% per year from 2011, at 527 per km² — the second-densest district in the province.

Bhojpuri is the district's lingua franca, spoken as a first language by half the population (50.9%), ahead of Nepali (28.8%) and Tharu (13.8%); Tharus (17.6%) and hill Bahuns (11.3%) are the largest communities of a thoroughly mixed plains society. The economy is built on paddy farming and on the roadside growth of Bardaghat and Sunwal, the market towns where the East–West Highway crosses the district; the headquarters Parasi lies south of the highway in Ramgram Municipality.

Seven kilometres south of Parasi, a grassy seven-metre brick mound on the bank of the Jharahi stream is Ramgram stupa, one of the eight original stupas in which the Buddha's corporeal relics were enshrined after his cremation. Buddhist tradition holds that Emperor Ashoka, who opened the other seven to redistribute the relics, was turned away here by a guardian naga — making Ramgram the only original relic stupa still intact and unopened, in what archaeologists consider the territory of the ancient Koliya republic, the clan of the Buddha's mother. Excavations by the Department of Archaeology and Durham University in 2023 uncovered Buddha-era monastery and pond structures beside the mound, which has stood on Nepal's UNESCO World Heritage tentative list since 1996.