Twmbarlwm, also known as Twm Barlwm, Twyn Barlwm or locally known as "the Twmp", the Nipple or the Pimple because of the mound that lies at its summit, is a hill situated 2 km (1.2 mi) to the northeast of Risca in South Wales. It is often mistakenly referred to as a mountain but is actually a hill due to being under 600 m (2,000 ft). It is 419 m (1,375 ft) high and is a well-known landmark throughout the region. It commands extensive views across what is now the M4 corridor, over Newport and Cwmbran - with part of it coming into Cwmbran - and out over the Bristol Channel.

Risca is a town in the Caerphilly County Borough and the historic boundaries of Monmouthshire in south-east Wales. Risca has a railway station, re-opened on the Ebbw Valley Railway in February 2008, after a gap of 46 years. It is split into two communities; Risca East and Risca West. It has a population of 11,700. Cardiff the capital of Wales can be reached in under 28 minutes from the nearby railway station of Risca and Pontymister station which reopened in 2008 after a gap of nearly 60 years.