Not to be confused with Riau Islands Province, a province of Indonesia.
The Riau Archipelago is the core group of islands within the Riau Islands Province in Indonesia, and located south of Singapore. Before the province of Riau Islands was formed, there was no ambiguity in term, however, in Indonesian both the archipelago and islands are referred to as simply "Kepulauan Riau", albeit the province may have the word "Provinsi" preceeding it. The island arch definition predates the province by over 200 years.
Historically they - along with Temasek (now Singapore) - were under the Johor Sultanate before the split through the Anglo-Dutch Treaty of 1824; it is quite possible Singapore itself was considered a part of this archipelago during this time. The name of this archipelago predated the province by over two hundred years, and historically did not include the Lingga Islands or Natuna Islands, which now belong to the province of the same name.
The main islands are Batam, Rempang, Galang, Bintan, Combol, Kundur, and Karimun. Tanjung Pinang located in the south of Bintan Island is the provincial capital. Tanjung Balai Karimun is an international port along with Tanjung Pinang.