Great Iyu Island (Pulau Tokong Iyu or Pulau Iyu Besar in Indonesian) is a small uninhabited island in the Strait of Malacca, about 4.5 km north-west of Little Karimun, about 50 km west of Singapore, and about 800 m south-west of Little Iyu Island.[1] The two Iyu islets are known as The Brothers.[1] The island belongs to the Karimun Regency of the Riau Islands Province of Indonesia.
Great Iyu measures about 250 by 150 m and its highest point is about 45 m above sea level.[1]