Mynydd Llysiau

{{Short description|Mountain (663m) in Powys, Wales}}

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

{{Infobox mountain

| name = Mynydd Llysiau

| photo = Llysiaynynydd.JPG

| photo_caption = Mynydd Llysiau from near Waun Fach. Behind are: Sugar Loaf (left) Pen Allt-mawr (right)

| elevation_m = 663

| elevation_ref =

| prominence_m = 40

| parent_peak = Waun Fach

| listing = Hewitt, Nuttall

| translation = mountain of the fruit

| language = Welsh

| location = Black Mountains, South Wales

| range =

| grid_ref_UK = SO215300

| topo = OS Landranger 161

| type =

| age =

| last_eruption =

| first_ascent =

| easiest_route =

}}

Mynydd Llysiau is a subsidiary summit of Waun Fach in the Black Mountains in south-eastern Wales. It lies halfway between Waun Fach and Pen Allt-mawr. It is a distinguished summit with a steep eastern face.

The summit, marked by a pile of stones, is long grassy ridge. To the south is Pen Twyn Glas, before which are two boundary stones that resemble grave stones.Nuttall, John & Anne (1999). The Mountains of England & Wales - Volume 1: Wales (2nd edition ed.). Milnthorpe, Cumbria: Cicerone. {{ISBN|1-85284-304-7}}.