The number of people living in cities and towns has rapidly increased over the past century, with more than half of the 7.8 billion total global population choosing to reside in urban settlements. Considering that urban areas represent less than 1% of the Earth's surface, this leads to a remarkable concentration of population in such environments. Worth noting is that many of the cities that exist now were not there only a few decades ago. This shows the rapid changes that urban environments have undergone over a relatively short period of time, with cities and towns growing not only in number but also in size, and thus becoming more influential on the global stage. It is therefore no surprise that industrial and commercial activities are nowadays primarily located in urban areas; for many countries these environments become the most important contributor to their gross domestic product.
With this context in mind, this chapter initially focuses on the phenomenon of urbanisation and how it contributed to the development of towns and cities around the world. It then turns the attention to urban tourism, one of the oldest forms of tourism that has been largely neglected by researchers and academics until only a few decades ago. It will also discuss the complex nature of urban tourism and the evolution of this field of study, while providing examples to guide the reader.