Rhydypennau is a hamlet in the Genau'r-glyn district of Ceredigion, Wales, approximately 4+1⁄2 miles (7.2 km) north-east of Aberystwyth.

All three places stretch in a long narrow strip along the main Aberystwyth to Machynlleth road (A487).

In his memoirs about growing up in Llanfihangel Geneu’r Glyn (Llandre), Pen-y-garn and Bow Street, Tom Macdonald (1900–80) recalls that the local pronunciation of Rhydypennau was ‘Rhypenne’.

[3] An early Bronze-age copper thin-butted flat axe was found to the north-east of Rhydypennau Bridge.

The axe has one smooth face, which is slightly hammered along its edges, whilst the other is irregular and shows traces of tooling.