Gate of St. George located on the southeast side of the Eleftheria Square (main square), close to the Archaeological Museum. For many decades, until recently, they were hidden under Eleftheria Square. Only recently, the gate was restored and opened.
Gate of St. George was built in 1565 and are part of the Venetian walls, built to protect the city from foreign invasion, and were used as a passage between the city and the port. Stone steps lead down to the gallery with a domed roof and then - to the lower output of the wall of the ancient Heraklion. This is all that remains today of the importance of the medieval entrance to the city.
The gate was also known as "gates Lazaretto", as they were to the House of Lazarus - hospital for infectious diseases on the east coast of the walls of Heraklion. The city was struck by a plague on several occasions, the most severe outbreak was in 1591-1593, respectively.
Gate of St. George is a monumental building with the original facade. On the city wall near the gate is a plaque from 1565, decorated with coats of arms and the initials of the leading Venetian families of the time. High above the gate was installed relief medallion of St. George on horseback. The majestic façade was destroyed in 1917, and a relief depicting Saint George kept in the Historical Museum of Crete.
Today Gallery Gate of St. George is often used for art exhibitions and other cultural events.
I can complement the description