In The House of the Spirits, the family's country estate is Tres Marías, also written as Las Tres Marías.
The estate is restored and transformed by Esteban Trueba, who turns neglected land into a prosperous hacienda through hard work, authoritarian control, and exploitation of its peasant workers. It becomes the main rural setting for several generations of the Trueba family and a place where personal conflicts reflect Chile's wider class and political divisions.
Blanca Trueba spends her childhood summers at Tres Marías, where she develops a deep relationship with Pedro Tercero García, the son of Esteban's foreman. Their romance crosses the rigid social boundaries enforced by Esteban and becomes one of the novel's central storylines. The estate therefore represents both family heritage and the unequal social order that the younger generation challenges.
The name is sometimes shortened to Tres Marías in summaries, while Las Tres Marías is the fuller Spanish form. It should not be confused with the family's urban residence, known as the big house on the corner. Isabel Allende published the novel in 1982.