Y mae Edern yn blwyf bychain, llawn tir pori, sy'n rhedeg a'r hyd arfordir Gogledd Orllewinol Llyn. (SH 17326) Mae'r penref ei hyn wedi ei leoli ar hyd y B4417 tua 1km i'r De Ddwyrain o Morfa Nefyn, rhwng y'r afon Geirch a'r hên groesffordd.

Edern is a small parish of mainly pasture land running along the north western coast of Llyn.(SH 17326). The village of Edern lies along the B4417 about 1 Km South West of Morfa Nefyn, between the river Geirch and the old cross roads.