Just mapped it. What the heck is a mumbles?
I've been wondering that! Maybe the native people to that region always mumbled the name of the place, so when the outsides came in and made the maps, they just called it "The Mumbles" as a joke.
Wikipedia says
this: "Mumbles has been noted for its unusual place name. The headland is thought by some to have been named by French sailors, after the shape of the two anthropomorphic islands which comprise the headland: the word 'Mumbles' may be a corruption of the French 'les mamelles', meaning 'the breasts'. Another possible source of the name is from the word Mamucium which is generally thought to represent a Latinisation of an original Brythonic name, either from mamm- ("breast", in reference to a "breast-like hill") or from mamma ("mother", in reference to a local river goddess)."
