Bontang

Bontang is a coastal city situated on the eastern coast of the island of Borneo in the Indonesian province of East Kalimantan. Geographically positioned between 117° 23′ E and 117° 32′ E longitude and 0° 01′ N and 0° 12′ N latitude, the municipality administers a total area of 497.57 square kilometres.

Within its administered borders, land makes up only 160.62 square kilometres, or roughly 32 percent of the total area. The physical terrain is defined predominantly by flat lands spanning elevations between 0 and 106 metres above sea level, interspersed with several hills. Approximately 48 percent of the land area is situated in coastal regions, maintaining a level character with a slope ranging from 0 to 2 percent. Soil composition varies across the territory, featuring podzol sediments in the interior and alluvium deposits along the coast, which renders the terrain susceptible to erosion and requires prior soil stabilisation for development or agricultural use. The city is part of the Kutai river basin, featuring geological formations dominated by quartz sand and sandstone created by sediment from nearby rivers.

Bontang shares its land and maritime boundaries with the Makassar Strait to the east. To the north and west, it is bordered by the Teluk Pandan District of East Kutai Regency, while the Marang Kayu District of Kutai Kartanegara Regency forms the southern border. Administratively, the city is divided into three districts: North Bontang, South Bontang, and West Bontang. Population density varies across these divisions, with North Bontang recorded as the most densely occupied district and South Bontang as the least dense due to a relatively unpopulated area located in its southern section. Across the entire municipality, the official mid-2025 population estimate reached 194,606 residents, making Bontang the third most densely populated place in East Kalimantan province, following Balikpapan and Samarinda.