Pen Pumlumon Arwystli

{{Short description|Mountain (741m) in Ceredigion, Wales}}

{{Use dmy dates|date=April 2022}}

{{Infobox mountain

| name = Pen Pumlumon Arwystli

| photo =

| photo_caption =

| elevation_m = 741

| elevation_ref =

| prominence_m = 64

| parent_peak = Pen Pumlumon Fawr

| listing = Hewitt, Nuttall

| language = Welsh

| location = Ceredigion, Wales

| range = Cambrian Mountains

| coordinates = {{coord|52.4750|-3.7458|type:mountain_region:GB|display=inline,title}}

| grid_ref_UK = SN789869

| topo = OS Landranger 135

| easiest_route =

}}

Pen Pumlumon Arwystli is the second highest summit on the Plynlimon massif, a part of the Cambrian Mountains in the county of Ceredigion, Wales.

The summit is grassy, and is marked by 3 large ancient cairns. The views include Rhos Fawr, Drygarn Fawr, Pen y Garn to the south and Aran Fawddwy, Glasgwm, Tarrenhendre and Tarren y Gesail to the north.

The longest river in Britain, the River Severn, has its source on a lower boggy plateau to the north of the summit.Nuttall, John & Anne (1999). The Mountains of England & Wales - Volume 1: Wales (2nd edition ed.). Milnthorpe, Cumbria: Cicerone. {{ISBN|1-85284-304-7}}.