Sultan Riau Grand Mosque is a famous historical tourist site on Penyengat Island, Tanjung Pinang, Kepulauan Riau province. This mosque was built when the island was the residence of Engku Puteri Raja Hamidah, wife of the Riau ruler, Sultan Mahmudsyah (1761—1812). Initially, this mosque was a simple wooden building with brick floors and about 6 meter tall towers.
Sultan Abdurrahman then invited participation from his people to help build a bigger mosque. People from many places around the Riau Lingga area came to the island to donate their materials, food and manpower.
Some said that due to abundant food supplies of rice, vegetables and eggs, workers were so bored eating eggs that they only ate the yolks and used the whites as adhesive material. The egg whites were mixed with sand and limestone to make this mosque which still stands strong today.