The interactions between the metal and its environment are responsible for the electrochemical reactions leading to corrosion. To avoid further degradation and in general the appearance of corrosion products, a corrosion inhibitor must be applied on the metallic surface to reduce or prevent the corrosion of exposed metal in a corrosive environment. Corrosion inhibitors are one of the different methods used by conservation-restoration professionals to preserve metallic cultural heritage. The present case study is concerned with preserve and controls the corrosion of the iron entrance door/gate of the clock tower of Muhammad Ali mosque at Salah Ed-din Cairo citadel, Egypt, which was erected in 1845 AD, by using an environmentally friendly Corrosion inhibitor. This inhibitor is of attentiveness since there has been a growth in ecological consciousness and a variation in guidelines that control the toxicity of systematic corrosion inhibitors. So, the natural products are becoming the main source of environmentally-friendly corrosion inhibitors. Furthermost their extracts comprising the required features of the traditional corrosion inhibitors such as oxygen, carbon, nitrogen, and sulfur. These elements are contributed to the adsorption process on the metal surfaces and arrangement of a protective layer, which shields the metal surface against environmental corrosion. Progress of green chemical knowledge compromises a new artificial approach for ionic liquids. These compounds are well-thought-out as new safe corrosion inhibitors which act in different corrosive conditions. Finally, applications of vapor-phase inhibitors and their role of action are recommended in the protection of iron windows under study.