It is home to Kampong Ayer, the Brunei's traditional village on stilts above the river water.
Some of Brunei's historical sites are located along the river banks, including: The river is also home to Jong Batu, a rock outcrop believed to be the remains of a ship belonging to Nakhoda Manis, a figure associated with the local legend of an unfilial son cursed into stone.
Both islands, Pulau Pilong-Pilongan and Lumut Lunting, have ties to a long-standing myth that dates back more than 500 years.
According to legend, the incident occurred in the early years of Awang Alak Betatar's first sultanate, somewhere in the 14th century.
In a cockfight, two carefully trained and conditioned roosters engage in combat as onlookers wager on the winner.
Raden Angsuka Dewa, who also owned Asmara, a rooster reputed to be comparable to Mutiara, learned about this.
Asmara disappeared from view, fell into the water unconscious from his wound, and transformed into a rock into an island (Pulau Pilong-Pilongan).
Elder Kampong Ayer residents have a saying that Lumut Lunting will never be submerged, no of how high the water level rises.