Situated on the banks of the Severn between Llanidloes and Newtown, the name of the village (population 1,600) refers to a Roman fort (‘Fort of Sws’); Swswen may have been a queen from Roman times. Caersws has a station on the Cambrian line from Shrewsbury to Aberystwyth. The Van Railway used to run from the village to the lead and silver mines that were located to the north of Llanidloes. Production peaked in 1876 when ore valued at over £100,000 (worth £8 million today) was mined. From 1868 until 1887, the manager of the Van Railway at Caersws was John Ceiriog Hughes, a Welsh poet and collector of Welsh folk tunes who did for Welsh poetry what Wordsworth and Coleridge did for English poetry.
The Church at the nearby village of Llanwnnog dates from either the C13th or the C15th; restored in 1863, it contains the best example of a rood screen and loft in Montgomeryshire, a medieval font bowl and a C17th memorial.
Caersws has a railway station on the Shrewsbury to Aberystwyth Cambrian line.