Introduction to the special focus Cultural tourism and sustainable urban development

In a world where more than half of the population already lives in cities and more than 90 percent of urban growth is occurring in the developing world (Licciardi and Amirtahmasebi, 2012), cities have the potential to serve as incubators of innovation and technology. However, there are also many challenges for cities that can be classified into economic, environmental, and social threats. Cities, for instance, consume 75 per cent of worldwide energy production and generate 80 per cent of CO2 emissions (Lazaroiua and Rosciab, 2012). The 'smart city' paradigm, which has been adopted by many cities worldwide, represents an environment where innovation and technology supplement activities and services of a city in order to provide benefits to the residents and visitors. In Europe, initiatives for sustainable development of cities have been characterised and defined by a number of factors including environmental sustainability, economic development and a high quality of life