A "Walled City" refers to a city or town that is surrounded by defensive walls. These walls were built to protect the inhabitants from invasions and attacks. Historically, many walled cities were established during the Middle Ages, and they often feature narrow streets, fortified gates, and towers. Examples include Carcassonne in France and Jerusalem in Israel. Today, some walled cities have preserved their historical architecture and attract tourists. They often showcase a blend of cultural influences and offer insights into the past. The walls serve as a reminder of the city's history and the challenges faced by its residents over the centuries.