Indonesia is the largest archipelago in the world comprising 17,508 large and small tropical islands, many still uninhabited and a number even still unnamed. There are five main islands (Sumatra, Java, Kalimantan, Sulawesi, and Papua), two major archipelagos (Nusa Tenggara and the Maluku Islands), and sixty smaller archipelagos. Two of the islands are shared with other nations; Kalimantan (known in the colonial period as Borneo, the world’s third largest island) is shared with Malaysia and Brunei, and Papua shares the island of New Guinea with Papua New Guinea. The total land area is 1,904,569 square kilometers. Included in Indonesia’s total territory is another 93,000 square kilometers of inlands seas (straits, bays, and other bodies of water). The additional surrounding sea areas bring Indonesia’s generally recognized territory (land and sea) to about 5 million square kilometers. Straddling the equator, situated between the continents of Asia and Australia and between the Pacific and the Indian Oceans, it consists of 33 provinces with 98 cities, and 399 regencies.

The main variable of Indonesia’s climate is not temperature or air pressure, but rainfall. Split by the equator, Indonesia has an almost entirely tropical climate, with the coastal plains averaging 28°C, the inland and mountain areas averaging 26°C, and the higher mountain regions, 23°C. The area’s relative humidity is quite high, and ranges between 70 and 90 percent. However, since Indonesia is located on the Ring of Fire, this archipelago is particularly vulnerable to the impacts of climate change and disasters such as earthquake, tsunami, and volcano eruption. According to socioeconomic condition outlined, Indonesia has the conducive situation to conduct programs and policies to alleviate slum areas. The increasing in HDI and GDP, also the decreasing in poverty can be a promising prospect to endorse municipalities in cooperating with private sector and community itself to create a decent living with slum upgrading programs. he Long-Term National Development Plan (RPJP), Law No.17/2007, determined that the main targets of the long-term housing development and settlements is “to meet the people’s housing and its infrastructures need and the aim of creating cities without slums, provision of housing as well as the necessary supporting facilities and infrastructure.