This was the new Hospital of the Knights and their original raison d’etre (reason for being). Begun in 1440, over the remains of a Roman building, it was not until the Grand Master d’Aubusson oversaw the project for over 40 years on that it was completed. It was built along similar lines to Byzantine hostelries and is one of the few examples of Gothic architecture in Greece.
The entrance opens into a courtyard, surrounded by a galleried upper story accessed by an outside stairway. Stone fragments and stacks of cannonballs, relics from various sieges, lie on the ground. During the Ottoman era it was used variously as a hospital then ignobly as a barracks. It was restored by the Italian administration in 1913-18 and later used to house the Rhodes Archaeological Museum. The Museum contains various collections of archaeological artifacts from various parts of Rhodes and the neighbouring islands.