Palace of the Grand Master of the Knights of Rhodes
Yes, the name is a mouthful, but the castle complex is just as impressive as its title. This medieval castle dominates the city of Rhodes, and is one of the few examples of Gothic architecture in Greece. Having been around since the 14th century, the palace is certainly the highlight of the Old Town.
The Palace of the Grand Master, home of the head of the Knights of Saint John, was badly damaged by an ammunitions explosion in 1856 but was restored to serve as a summer home for Mussolini. The atmospheric interior includes floor mosaics, statuary, paintings, chapels and a wealth of artifacts. Marble floors and vast spaces keep the inside temperature markedly cooler than outside, a boon for summertime visitors.