Abstract
There is a huge pressure on infrastructure in metropolitan cities, transit system are bursting at its need these systems are unable to expand with the growing ridership, no country can claim to be free of informal settlements. Cities are unable to increasing the size of the present infrastructure. The situation will be worse by 2050 as 70% of the world population will be living in urban areas (Nation, 2014). The average size of the world’s largest 100 cities, have grown from 200,000 in 1800 to 5.1 million in 1990 and in million now. To serve this fast growth cities like Hong Kong New York Singapore etc. Have high rise structures. These metropolitan cities have scarcity of undeveloped land the only option remain for these cities to survive is to go down. Although living underground is an old concept of about 1500 years at least which exist in the Cappadocia region of turkey. (Ömer Aydan, June 2003), now a days this concept has started with the earth summit habitat II in 1996 which talks of utilizing 3rd dimension of the city by development of infrastructure on high land value surfaces of city. Projects such as Mexico earth scrapers (65 stories inverted pyramids building), low line park are effective way to serve daily rhythm of city life. This is truly a new approach to escalating megacity problems like planning for population growth, preserving open space, modification mix-uses spaces, adding economic value and conserving energy and water. The paper will check the sustainability of underground spaces and recognize the parameter to understand the climate (humidity, temperature, access of sunlight) of these spaces by considering example of proposed project.
