Y Fronllwyd, also known as Carnedd y Filiast North Top, is a top of Carnedd y Filiast in Snowdonia, Wales forming part of the Glyderau. It is the northern end of the Glyder mounatin range. The summit has good views of Bethesda, the Penrhyn Quarry, the Carneddau, Elidir Fawr and the Menai Strait.