Kalimantan is the eastern and Indonesian part of Borneo, occupying almost 80% of the island's total area and having a population of about 13.6 million. The largest cities in eastern Borneo include Banjarmasin, Pontianak, Balikpapan, Samarinda and Loa Janan.

Kalimantan is crossed in the middle by the equator and has the third largest contiguous tropical rainforest in the world. This vast area provides habitat for several species of mammals, such as orangutans, gibbons, pygmy elephants, monkeys and several species of wild cats.

Nowhere in the world are there more different types of orchids than in the eastern part of Borneo, including the strictly protected black orchid.

There are significant oil reserves off Kalimantan and form an important part of Indonesia's export economy.

In May 2018, I traveled to the city of Balikpapan in Indonesian Borneo for two days. I started the two-hour flight from Jakarta with Garuda Indonesia. As soon as I arrived at the airport, the people were super friendly and gave me important information about the city. Although the Indonesian part is not particularly touristy compared to the Malaysian Borneo areas, there was still a lot to see in the city. For only 20 US dollars, I booked a three-hour city tour right at the airport with what was supposed to be the best city guide in all of Balikpapan. The city is primarily determined by its oil industry and offers the majority of the population enough work and social security. Balikpapan is very clean throughout the cityscape and, to my surprise, quite pleasant for tourists.

The city's important sights include several colorful mosques, some large churches and various sandy beaches.

The next morning I took Lion Air to Palu on the island of Sulawesi.