The "Palacio Arruabarrena" was built in 1919, as a family home, with materials brought from Europe. The work began in 1916 with plans by the architect Gabriel Dulin and the builder Luis Pepey. It belongs to the eclectic style with French reminiscences in the mansard roofs.

The idea of ​​building a house with such refined architecture was born on a trip to France made by Juan Bautista Arruabarrena, in the first decade of the 20th century. Arruabarrena stayed in a residence whose design struck him for its beauty and stateliness, sparking his interest in building a similar building in Concordia. Since January 1984, the building has been used as the seat of the Municipal Regional Museum “Palacio Arruabarrena”. The Museum offers the visitor the possibility of delving into the history of Concordia and the Region.

It has an important collection of objects: furniture, utensils, clothing, ancient weapons, coins, photographs, etc.; organized in different thematic rooms that are exhibited in its permanent exhibition.