Heraklion is the largest city and administrative capital of Crete, Greece. It has a population of over 225,000. The historic Koules Fortress, built by the Venetians in the 16th century to defend against the Ottomans, dominates the harbor. Saint Titus Cathedral was originally built as the city's cathedral during Byzantine rule and has since served as a Catholic church and mosque during different periods. Lion Square is the heart of the city, centered around a decorative fountain decorated with mythological figures and supported by stone lions. The Archaeological Museum houses artifacts from across Crete, most notably the treasures of the ancient Minoan civilization.