East Kalimantan

East Kalimantan is a major province located in Indonesia. It covers the eastern portion of the island of Borneo, also known as Kalimantan.

The province serves as a primary gateway to the eastern parts of the country. It is a region defined by its diverse geography, including many hills and numerous lakes. The largest lakes, Semayang and Melintan, are located within the Kutai Regency.

The province also contains hundreds of rivers. The Mahakam is the longest river in the region. These waterways are vital for transportation alongside land routes.

The geography of East Kalimantan is quite complex. The province has a total land area of 125,336.81 square kilometers. It also manages an ocean area of 25,656 square kilometers. To the east, the province shares a maritime border with West Sulawesi and Central Sulawesi. The large Mangkalihat Peninsula sits in the east, separating the Makassar Strait from the Celebes Sea. To the west, it shares land borders with West Kalimantan, Central Kalimantan, and the Malaysian state of Sarawak. In the north, it borders the province of North Kalimantan. To the south, it borders South Kalimantan.

The climate in East Kalimantan is tropical. This means the region experiences two distinct seasons: a dry season and a rainy season. The dry season typically runs from May to October. The rainy season usually occurs from November to April. These seasons are influenced by monsoon winds. West and east monsoons affect the area during these specific months. In recent years, the weather has become somewhat erratic. Sometimes it does not rain during the expected rainy months. Other times, it rains heavily during the dry season.

Temperature and humidity levels are also characteristic of the region. The climate is generally hot. In 2013, temperatures in Berau ranged from 21.6 °C to 35.6 °C. The air is often very humid due to the extensive forests. Average humidity levels in 2013 were between 83 and 87 percent. The highest humidity recorded was 91 percent in Berau in February. Rainfall also varies by location. In 2013, the highest average monthly rainfall was 245.1 mm in Berau. The lowest average was 237.8 mm in Samarinda.

East Kalimantan possesses an incredibly deep history. In prehistoric times, people lived in limestone caves. The Lubang Jeriji Saléh cave is located in the Sangkulirang-Mangkalihat Karst. Scientists discovered figurative art there in 1994.

By using dating techniques on calcium carbonate deposits, researchers identified these paintings as some of the oldest in the world. They are estimated to be over 40,000 or perhaps 52,000 years old. Later, the region became home to many powerful kingdoms. The Kingdom of Kutai Martadipura was the first and oldest Hindu kingdom in Indonesia. It was founded in the 4th century CE.

Political boundaries in the region have changed many times. In the 19th century, the Sultan of Banjar handed these territories to the Dutch East Indies. The province was officially established by Law No. 25 of 1956. At that time, it only had three special regency-level regions: Berau, Bulongan, and Kutai. The number of administrative divisions grew steadily over the following decades. In 2012, the northern part of the province was split off. This created the new province of North Kalimantan. Today, East Kalimantan is divided into seven regencies and three cities.

The economy of East Kalimantan is heavily tied to its natural resources. The region is known as a storehouse for timber and mining.

Mining and petroleum are very important to the local economy. Additionally, a massive modern project is currently transforming the province. The Indonesian government is constructing a new national capital city named Nusantara.

This city is being built across parts of Penajam North Paser and Kutai Kartanegara. Although the project faced budget changes during the COVID-19 pandemic, the new capital was formally inaugurated in August 2024. This makes East Kalimantan a central location for the future of Indonesia.