Townhill to Cwmbwrla , Penlan , Treboeth and Fforestfach ; through Uplands , Sketty , Killay to Dunvant ; and east of the river from St. Thomas to Bonymaen , Llansamlet and Birchgrove . A second urbanised area is focused on a triangle defined by Gowerton , Gorseinon and Loughor along with