Caerphilly.

Caerphilly is a valleys seat in south-east Wales built around a network of former mining towns rather than a single dominant centre. The town of Caerphilly itself is the largest settlement at roughly 32,000 people, about a third of the seat, with Ystrad Mynach, Pontllanfraith and Bedwas forming a chain of smaller towns down the valley and a scatter of villages such as Nelson, Llanbradach and Senghenydd beyond. The population of about 101,600 is older than the national average, overwhelmingly White, and below the national mean for degree-level education. Local services across all fifteen wards in the seat are run by a single Welsh unitary authority, Caerphilly County Borough Council.

The local political picture has tightened markedly. Across the most recent ward contests Plaid Cymru and Labour now sit almost level, with Plaid edging ahead on the latest count and taking several seats outright, a shift from Labour's long dominance of the valley. The parliamentary figures still favour Labour: at the 2024 general election the party held the seat on 38 per cent, with Plaid Cymru the runner-up on 21 per cent, though that margin had narrowed sharply from 2019. Chris Evans, the sitting Labour and Co-operative member, has held the seat since 2010 and speaks most often on the economy, defence and social care; on the figures available he sits within his party's mainstream.

The direction of travel appears to be away from Labour and toward Plaid Cymru, with recent contests increasingly competitive rather than settled. Coverage of the council in recent months has tended to dwell on financial strain and difficult budget choices, alongside steady reporting on town-centre regeneration. The combination leaves a seat that has long looked safe for Labour now looking genuinely contested, with the next round of elections likely to test whether the parliamentary result follows the local one.