Looking at Google Maps I noticed when translating to Japanese some names are hyphenated and others are not. It seems to be arbitrary but maybe there's some Japanese rule I'm unaware of
The first example I noticed is "Daikan-Yama" which at first I thought, "Okay, that's strange" but then I thought, "well, I guess if you think of it as Mount Daikan then it might make sense".
But there's is apparently no rhyme or reason as to when something is hyphenated. Followed the "Daikan-Yama" example I'd expect "Sangu-bashi" as in "Sangu Bridge" or "Aka-saka" as in "Red Hill" or "Shibu-Ya" as in "Shibu Valley". We see "Higashi-Kitazawa" for "East Kitazawa" but we don't see "Shimo-Kitazawa" for "Lower Kitazawa".
Is there any actual rule or is it just arbitrary?