On its western side, the Halmahera Sea includes three large gulfs or bays which cut deep into the coast ofHalmahera island, turning the east coast of that island into four huge peninsulas. These three inlets compriseWedi Bay (Teluk Wesi) in the south (between the southern and southeastern peninsulas),Buli Bay (Teluk Buli) in the centre (between the southeastern and northeastern peninsulas) andKao Bay (Teluk Kao) in the north (between the northeastern and northern peninsulas). A notable fourth inlet isGalela Bay (Teluk Galela) further to the north, which projects into the coast ofNorth Halmahera Regency.
On the North A line from Wajaboela (Morotai) to Tg. Djodjefa, the Northern point ofHalmahera.
On the East. A line from Tg. Gorango, the Northeastern point of Morotai Island, through Sajang and Kawé Islands to the Western extremes ofWaigeo andBatanta Islands across to the Northwest point of Samawati Island, down the coast to Tg. Menonket its Southwest point, and thence to Tg. Sele,New Guinea (1°26′S130°56′E / 1.433°S 130.933°E /-1.433; 130.933).
On the South. The Northern limit ofCeram Sea betweenObi Major and New Guinea [A line from ... Obi Major ... Tanjong Seranmaloleo its Eastern extreme, thence through Tobalai, Kekek, Pisang andKofiau Islands to Tanjong Sele (1°26′S130°55′E / 1.433°S 130.917°E /-1.433; 130.917), the Western point of New Guinea].
On the West. The Southern limit ofMolukka Sea [sic] between Halmahera and Obi Major [A line from the Southern extreme of Halmahera to the North point of Bisa (Setile) Island, thence to the Northern extreme of Obi Major].
