Tarakan is an island and co-extensively the sole city within the Indonesian province of North Kalimantan. The island city is the largest urban area in North Kalimantan population-wise and is located in northern Borneo, midway along the coast of the province. The city boundaries are co-extensive with the island. Once a major oil-producing region during the colonial period, Tarakan had great strategic importance during the Pacific War and was among the first Japanese targets early in the conflict. It is the sole city within the newly established Indonesian province of North Kalimantan. According to Statistics Indonesia, the city had a population of 193,370 at the 2010 Census and 242,786 inhabitants at the 2020 Census; the official estimate as at mid 2023 was 249,960.

Borneo is the third-largest island in the world, with an area of 748,168 km2 (288,869 sq mi). Situated at the geographic centre of Maritime Southeast Asia, it is one of the Greater Sunda Islands, located north of Java, west of Sulawesi, and east of Sumatra.