The architecture of the capital of Corfu has been shaped over the centuries, under Venetian, French and English rule. The unique old town has been protected by UNESCO as a World Cultural and Historic Heritage Site. Kerkyra is a city containing monuments and buildings from almost every era. The most ancient ones date back to the 6th century BC. The miraculously surviving pediment of the ruined, majestic Temple of Artemis is the greatest antique find of the 20th century. The first opera house and the first university in Greece were built on Corfu. The city of Corfu has the largest square in Greece, and the Palace of Saint Michael and George houses a collection of significant pieces of Asian art.