The city walls of Piran were mentioned as early as the 7th century when they were built surrounding the old city core in Punta. Since then the city has grown towards Mandrac, including more and more quarters that were originally formed outside of the walls. Due to the growth of the city and in order to protect it from enemy attacks, two additional parts of the wall were built, including several defence towers. Its largest preserved section known as Mogoron holds an incredible historical value.
Seven gates that used to be the entrances to the city remain preserved in Piran: The Milje Gate (9A), the Dolfin Gate (9B), the Field Gate (9C), the Baroque Gate of St. George (9D), the Marčana Gate (9E), the First Rašpor Gate (9F) and the Second Rašpor Gate (9G). The Milje Gate (9A) is among the oldest preserved gates in the city. The Dolfin Gate (9B) is the nicest Gothic gate in the city, and dates back to the 15th century when the mayor of the city at the time, Dolfin, had them made. They are easily recognised by a crest depicting three dolphins.