North Kalimantan is a brand-new province carved out of the top of East Kalimantan. It includes the island of Nunukan (not to be confused with the one in the Derawan Archipelago) Sembakung, Bulungan, Tanjung Selor, Tarakan, Krayan, Kayan Mentarang and the Apokayan. This area includes some of the most pristine forests on Borneo, making it one of the last frontiers for hardcore jungle trekking. Only a handful of people have crossed the vast jungle of Kayan Mentarang.
The most common reason for travellers to pass through North Kalimantan is on their way to or from Malaysian Borneo. At time of research the direct ferry from Tawau (Sabah) to Tarakan wasn’t operating, but there is a speedboat service from Tawau to Tarakan (140,000Rp, four hours) via Nunukan (two hours) where you switch boats. The boat leaves Tawau at noon, but show up an hour early to clear immigration and ensure a seat. Save five ringgits for the terminal fee. The quicker but more expensive route is the daily MASwings flight from Tawau to Tarakan (550-800,000Rp).
To get from Tarakan to Berau/Derawan Archipelago, take an early morning boat to Tanjung Selor (80,000Rp) and then a car from the harbour (55,000Rp to 75,000Rp). For air tickets see Angkasa Express (055130007) or Derawan Travel. The Immigration office has information on visas. If you need to stay over, Hotel Bungamuda is a good budget option, while Swiss-Belhotel Tarakan is an upscale bargain.