The Sjønstå River runs into the lake here, and where it does, glacial moraine left a set of natural terraces above a beach of pale sand — the only decent farmland for some distance in any direction. Somebody claimed it in the seventeenth century. The place first appears in writing in a rent roll of 1665, spelled Süinstad, with a tenant named Baard Pedersøn; it is missing from the land committee's register of 1661 and from the tithe list of 1663–65, which suggests the farm was established more or less exactly when the document was drawn up. The name itself is a puzzle. The philologist Oluf Rygh proposed that it came from skinstøde-å, with å meaning 'river' and the first element naming a place where cattle habitually shelter from the summer heat and the bot flies. Locally people have always said Sjønståg, or Skjønståga, or Sjønstaa. Clerks in distant offices spelled it however they liked.

Then, from 1891, Swedish and Norwegian capital opened copper and pyrite mines at Sulitjelma, up in the mountains against the Swedish border, and the ore had to get out. The route it took was absurd and unavoidable. Boats carried it the length of Langvatnet from Sulitjelma to Fossen. From Fossen a narrow-gauge railway, built in 1892, ran it down to Sjønstå. At Sjønstå it went back onto the water — down Øvervatnet, then Nedrevatnet — and only at Finneid did it reach a quay on Skjerstad Fjord where a ship could take it. Sjønstå was the hinge in the middle: the place where a trainload became a boatload. That required people, and the right people — locomotive crews, boatmen, mechanics, warehousemen, a station master. A farm of a few families became a junction of a few hundred.

At its height Sjønstå held about 300 residents, and they did what northern industrial villages did: they founded things. A lodge. A shooting club. A sports club, in 1916, which lasted longer than the reason for its existence. A school opened in 1899 and ran for sixty years. There was a general store, a locomotive shed, and from 1936 a Folkets hus — a people's house, the workers' hall that in Norway usually meant a labour movement had arrived and intended to stay. It is worth remembering how quickly this all came and went. A man who was born on the farm before the mines opened could have watched three hundred neighbours arrive, a railway and a fleet of lake boats appear, and every one of them vanish again, and still not have reached old age.

The farm outlasted the village because nobody ever had reason to modernise it. Sjønstå is a klyngetun, a cluster farm — buildings crowded together in a tight, almost village-like knot rather than spread across the holding. The layout was ordinary in Nordland before 1900 and is now almost entirely gone; Sjønstå is the only one left in Northern Norway. There are about twenty structures, divided between an inner farm of four dwelling houses and four raised granaries, or stabbur, and an outer farm of cowshed, storehouse, barn, woodshed and stall. They have not substantially changed since the 1800s. The Norwegian Directorate for Cultural Heritage gave the site protected status in 2006, citing both the rarity of the layout and its entanglement with the Sulitjelma mines. A foundation set up in 1987 looks after it, and roughly six million kroner went into restoration work between 2003 and 2013. Nobody lives here permanently. In summer the Folkets hus opens as a café, which is a strange and rather good afterlife for a workers' hall.