Balikpapan is a seaport city on the eastern coast of the island of Borneo, in the East Kalimantan, a resource-rich region well known for its timber, mining, and petroleum export products. Two harbors, Semayang and Kariangau (a ferry harbour), and the Sepinggan International Airport are the main transportation ports to the city. The city has a population of 639,031, making it the second-largest city in East Kalimantan, after Samarinda.