Penpergwm is a village in south Wales, situated along the A40 road, 3.9 miles (6.3 km) south-east of Abergavenny and 14 miles (23 km) west of Monmouth.

The site of Castell Arnallt lies on a mound in the water meadows between the village and the River Usk.

[1] The village used to have to a railway station on the Welsh Marches Line, but it closed in 1958.

[2][3] The former station house is now a private residence.

[4] The former British politician Francis Pym was born in Penpergwm Lodge in the village.