An exciting and easy to grasp concept of the future is the notion of a megacity of gargantuan proportions. An urban population of one hundred million no longer seems unrealistic. Two hundred years ago, there was only one city with the population of over one million people – Beijing. By mid-20th century, as Richard Florida notes in his recent book, there were 83 cities with the population of over one million and two megacities whose population hit ten million. Today there are 28 megacities, by 2030 the number will grow to 40, and by mid-22nd century there may be ten megacities with the population of 50 to 100 million people. New research suggests that by 2100, Lagos, a port city in the south of Nigeria, will be home to 85 to 100 million people. Such rapid growth will bring about new-level problems and challenges in almost every sphere, from management and environmental protection to infrastructure, migration and mental health.