Ungwana Bay (formerly known as Formosa Bay) extends from Ras Ngomeni in the south to Ras Shaka in the north. The Sabaki River flows into the bay in the south, and the Tana River flows into the bay in the north. Because of the discharge of sediment from these two rivers - the conditions for coral formation are poor, hence there are no coral reefs in the bay. The dominant features of the Ungwana Bay coastline are sand dunes, and long stretches of sandy beaches.
There are no major holiday resorts along this stretch of coastline.