Bunnefjorden is the part of Oslofjorden placed east of Nesodden. North east part is in Oslo and the south part in Ås, Frogn and the middle part is in Nesodden and Oppegård.
Bunnefjorden has a very long water residence time and the water is of poor quality.
The significant islands in Bunnefjorden is Langøyene, Malmøya, Ulvøya, Ormøya, Gressholmen and Husbergøya.