This paper studies the way in which modern land-forest map design contributes to the protection of urban forests generally and the Seich Sou urban forest of Thessaloniki in particular. We also examine the role of cadaster and forest maps in protecting urban forests from abuses such as pressure for housing, which are particularly acute due to their proximity to urban centers. Particular emphasis is given to the Seich Sou urban forest, which provides important protection from erosion and pollution to the city of Thessaloniki. Thessaloniki is characterized by a low proportion of green areas per inhabitant and a high pollution burden. The history of the forest, its ownership status, its legal framework of protection, the problems it faces, as well as the role of the cadaster and forest maps in their resolution are presented. Finally, we conclude by proposing ways of strengthening the protective framework governing Seich Sou, as well as the urban forests of the country in general. The rational management of urban forests via the development of good forest policy with tools such as cadaster and forest maps can be the key to protecting urban forests effectively and exploiting their multiple benefits in perpetuity.