One of the basic principles of the 1967 Gazetteer, and ours today, is that settlement names (cities, towns, villages and hamlets) are usually written as one word.
Un o egwyddorion sylfaenol Rhestr 1967, a ninnau heddiw, yw bod enwau aneddiadau (yn ddinasoedd, trefi, pentrefi a phentrefannau) yn cael eu hysgrifennu fel arfer fel un gair.