Cardiff South and Penarth is a constituency of the Senedd. It elects one Member of the Senedd by the first past the post electoral system. It is typically a safe Labour seat.

Sully is a village in the community of Sully and Lavernock, in the Vale of Glamorgan, Wales, lying on the northern coast of the Bristol Channel, midway between the towns of Penarth and Barry and 7 miles southwest of the Welsh capital city of Cardiff.