Undella Bay (Japanese: サザナミ湾Sazanami Bay) is a small area in the eastern part of Unova. It is east of Undella Town and is the only way to access the Abyssal Ruins. In Black 2 and White 2, it connects Undella Town to Seaside Cave, which leads to Route 21.
In Black and White, Undella Bay appears on the Town Map as a green dot, like other landmarks, but in Black 2 and White 2, it appears as a line segment, as if it were a route. Similarly, the Desert Resort also appears as a line segment; however, it is also a line segment in Black and White.