The Auberge of Castille, Leon and Portugal, is the largest and perhaps finest of all the Auberges. Its head was the Grand Chancellor of the Order of St. John.

It was first built in 1574 by Girolamo Cassar on a site originally earmarked for the Magisterial Palace. Extensive reconstructions were taken in 1744 during Grand Master Pinto de Fonseca’s term of office. Domenico Cachia, the architect responsible for these modifications was influenced by the Profettura at Lecce and produced a very imposing façade.