St Mellons village began as a small commercial centre in the historic county of Monmouthshire, relying heavily on rural agriculture, farming and travel.

One of these bishops is known to have been born and brought up in the area where the estate now exists, though stories of the two have become hopelessly confused in many biographies over the years leaving historians unsure as to which is which.

Eurwg is said to have lived on the hill at St Mellons during the Romano-British era, he and his people were converted to Christianity and baptised in the nearby Rhymney River.

The other complex, located approximately one mile away, has among others, two previously empty supermarket units which once belonged to Hyper Value and Kwik Save until both companies went into liquidation in 2006[7] and 2007.

[11] There are also four public houses situated in close proximity along Newport Road: The Church Inn, The Poachers Arms, Ty'r Winch and The Fox & Hounds (widely believed to be one of the oldest pubs in Cardiff).

There are no learning institutions in this suburb for secondary, tertiary or higher education students (other than for fee-payers at St John's College).

Much of the newer estates were built on the Wentloog Levels, areas of low-lying farmland which regularly became flooded until they were reclaimed from the sea during Roman times.

Despite large scale development, a lot of wildlife can still be seen especially to the eastern fringe: foxes, rabbits, grey squirrels, buzzards, herons, egrets, moorhens, swans, mallards, green woodpeckers and many other birds are a common sight.

[14] Hendre Lakes Business Park is a large commercial property scheme proposed on land to the east of St Mellons by Cardiff Parkway Developments.

In 2007, a number of road-related deaths led to residents campaigning that traffic calming measures be implemented before more lives are lost.

[18] In late 2008, Cardiff Council began implementing new traffic calming measures outside the primary schools, including zebra crossings and speed bumps.

[citation needed] The road is planned to be built in low-lying marsh land, which is a designated Site of Special Scientific Interest (SSSI).

There is no local railway station, despite Hendre Lake park being adjacent to the Freight Terminal Port, situated along the main line between Cardiff and Newport.

In July 2017, Transport Secretary Chris Grayling gave his backing to a privately financed £25 million station at St Mellons, to be known as Cardiff Parkway.

[20] Planning permission was granted in 2022, but the Welsh Government intervened with a review, citing the broader national interest of the project.