As we approach the end of the second decade of the twenty-first century—at the moment when more people live in the cities than anywhere else—there comes a time to ponder on the role and the condition of urban cultural heritage. In times of growth, urbanization and rapid development, the city may be described as a modern battlefield of cultural heritage protection, often faced with the choice between protection and conservation, or destruction and redevelopment. This article seeks to analyse the means of protection of urban cultural heritage—a common, which is local (it takes a vital part in the creation of identity) and global (it is a part of a universal heritage) at the same time—in the international law, and to look into ways of its successful management. The first part of the article looks at the concept of the urban cultural heritage, and the second part examines the two main UNESCO conventions concerning cultural heritage protection, namely, Convention Concerning the Protection of the World Cultural and Natural Heritage and Convention for the Safeguarding of the Intangible Cultural Heritage, to establish whether or not they are successful tools in protecting the urban cultural heritage. The third part focuses on analysing a new approach towards urban cultural heritage advocated by UNESCO, based on the 2011 recommendation on the Historic Urban Landscape (HUL), giving examples of its successful (Amsterdam, Ballarat, Cuenca) and unsuccessful application (Stockholm, Hong Kong, Macau). In the fourth part, the author suggests ways of effective governance of the urban cultural heritage in the twenty-first century, from the viewpoint of sustainable urban development, focusing on the role of cultural heritage in the city’s growth, and in the creation of identity and collective memories. The concluding part of the article seeks for an answer to the question of a need for a new UNESCO convention.