A watch-tower is a tall structure used to keep watch over an area. It is also called a lookout tower or observation tower. Other synonyms for watch-tower include guard tower, lookout post, sentry box, and observation post. A watch-tower can be made of various materials like concrete, wood, or metal, depending on the purpose and location. It is commonly used in military outposts, prisons, and along borders to monitor activities and prevent unauthorized access. A watch-tower is an important structure that provides security and safety to the area it overlooks. It serves as a valuable tool for surveillance and intelligence gathering, making it an essential part of many operations.