Internal water is a concept of maritime zone priory recognized at the early development of sovereign territories at sea. The concept of sovereignty in internal waters is similar to the concept of sovereignty on the land that archipelagic states have full sovereignty over their archipelagic waters. There are no other states’ rights in such water zone. Unlike the case with other sovereignties, such as archipelagic waters (even though it is equally sovereign in these waters), other states have rights such as the right of innocent passage, the right to lay submarine cables, traditional fishing right and other noted rights. For such mandated reasons, it is essential for an archipelagic state such as Indonesia, which has 17,508 islands, to quickly assign internal waters delimitation in all islands to control of violation such as smuggling, trafficking, illegal fishing, so forth. Delimitation is important considering the position of internal waters within the archipelagic waters area, thus it requires the delimitation of internal waters to separate internal waters from archipelagic waters. This is important with regard to prevent overlapping and violation of the archipelagic state’s full sovereignty in its inland waters.