Old St Mellons (Welsh: Pentre Llaneirwg) is a village and community on the eastern edge of Cardiff, Wales.

This soon became the permanent home of the school, and one they occupied until moving to a new, purpose built building on Bridge Road, Old St. Mellons.

Because St Mellons lay in Monmouthshire, it also avoided having to abide by the Welsh Sunday Closing Act.

[5] Old St Mellons was designated a Conservation Area in 1976, giving Cardiff Council statutory powers to prevent certain changes, while preserving and improving the historical character of the village.

Old St Mellons elects a community council, comprising seven councillors, with two further seats available for co-option (April 2020).

Plans were unveiled in 2014 to build yet more modern housing on open fields within the Old St Mellons community.