Notes
This is the form recommended in the national standard reference work, A Gazetteer of Welsh Place-Names (University of Wales Press, 1967). One should not deviate from its recommendations without good reason.
It is recommended that both forms are adopted as both are well-established.
The name of a settlement is usually written as one word in order to distinguish between settlements and topographical features.
The hyphen is used in Welsh place-names in order to aid pronunciation by showing that stress does not fall on the penultimate syllable. The stress falls on the final syllable of this name and therefore the final syllable is preceded by a hyphen.