Arauca_Department Arauca is a department of Colombia located in the extreme north of the Orinoco part of Colombia (the Llanos Oriental), bordering Venezuela. It is bordered to the south by the Casanare River and the Meta River, which separate it from the departments of Casanare and Vichada. To the west borders with the Boyacá Department. The Caño Limón oil fields located in its territory accounts for 30% of Colombian oil output. Its capital is the town of Arauca.