Wilgena's story is, at bottom, a story about water. The McBrides bought the lease in 1923, reverting it to sheep after a spell running cattle, and built their flock on artesian bores that pulled ancient water up through the rock. By 1954 the station spread across roughly 3,000 square miles and carried about 45,000 sheep, fed by what one account called a plentiful supply of artesian water. But long before any borehole, this land kept its own reserves. Scattered across the property are rock holes, natural basins in the stone that catch and hold rain. They were of deep significance to the Aboriginal people of this country, who knew exactly where water could be found in a landscape that to outsiders looks uniformly dry. Two of the larger ones still carry their names, Adelbing and Coolbring, holding thousands of litres long after the surrounding plain has gone to dust.

Near Wilgena's heart sits Tarcoola, and the relationship is unusual: the station all but surrounds the town. Tarcoola was born in a gold rush after a prospector named Nichols struck the metal here in October 1893, the same year a racehorse called Tarcoola won the Melbourne Cup and lent the place its name. The goldfield's heyday ran from about 1901 to 1918, and over the following decades the diggings produced only a few tonnes of gold before fading. Today the town is all but deserted, kept alive by the railway alone. The Trans-Australian line runs straight through the property, and Tarcoola survives as a junction where the tracks split toward Perth, Darwin and Port Augusta, a lonely crossroads in the saltbush.

Long before the McBrides, the lease passed through a parade of owners chasing the same gamble. In 1882 it went to auction stocked with just 400 head of cattle. By 1884 it covered more than a thousand square miles, and new wells were being sunk to water an estimated 40,000 sheep. Owners came and went, prices rose and fell. In 1918 the whole run sold to Joseph Timms for fourteen thousand pounds. Four years later Timms offered it to the government for soldier settlement, a scheme to give returning servicemen land of their own; the offer came to nothing, and the McBrides bought instead. A century on, the family still holds the property, though it was split in the 1980s, with the neighbouring North Well Station carved off as a separate enterprise. The fence that once ringed the world's largest flock no longer encloses a single run, but the merinos, and the wool, remain.