We will like to call cities that enable such capabilities as, "semantic cities." In a semantic city, available resources are harnessed safely, sustainably and efficiently to achieve positive, measurable economic and societal outcomes. Enabling city information as a utility, through a robust (expressive, dynamic, scalable) and (critically) a sustainable technology and socially synergistic ecosystem could drive significant benefits and opportunities. Data (and then information and knowledge) from people, systems, and things is the single most scalable resource available to city stakeholders to reach the objective of semantic cities. Two major trends are supporting semantic cities -- open data and semantic web.