evidence: Ankoko Island (Spanish: Isla de Anacoco) is an island located at the confluence of the Cuyuni River and Wenamu River, at 6°43′N 61°8′W / 6.717°N 61.133°W, on the border between Venezuela and the disputed area of Guayana Esequiba. Venezuela, which claims Guayana Esequiba as part of its territory, established a military base on the island in 1966, which Guyana claims as intrusion and aggression on a territory whose sovereignty was never under discussion.