The bay branches off Davis Strait to the east, just north of Sisimiut.

It is navigable in its entirety, protected from the open sea by a series of skerries and channels in the west.

In the past, at the time of the Saqqaq culture settlements in the area, the bay extended further inland, the shoreline was up to several dozen meters above the present line, covering portions of the Sisimiut valley, and gradually decreasing in time due to post-glacial rebound.

Sisimiut Airport is located at the far western end on the northern side, behind the several skerries and small islands of Qeqertarmiut and the Annertusoq skerry group protecting it from the storm waves of the open sea, and separating it from the mouth of Amerloq Fjord in the southwest.

Both the commercial port and the harbour are located on the southern shore of the bay, on the mainland.