The Auberge de Castille, León and Portugal is the grandest of the surviving auberges of the Knights of St John in Valletta, and it now serves as the office of the Prime Minister of Malta. The current building dates from 1744, when it was rebuilt in the Baroque style under Grand Master Pinto de Fonseca, whose coat of arms adorns the elaborate facade. The building stands at the high point of Valletta near Castile Square, with the facade oriented toward Merchants Street below.
The interior is not open to public visits as it is an active government building, but the exterior facade is one of the finest pieces of Baroque architecture in Malta. The square in front of it, Castile Square, is a good vantage point for the harbour on the south side of Valletta and for views down Merchants Street toward Fort St Elmo.