After his son took over the title he preferred to live in Cardiff Castle, so demolished the house in 1815, and turned Cathays Park into purely enclosed parkland for grazing.

A major carriage and wagon construction and maintenance facility, it and the associated locomotive depot were taken over and maintained by the Great Western Railway.

A popular local charity, one of its many benefactors was the boxer Jim Driscoll, who, since his burial in Cathays cemetery in 1925, has had his grave tended by the nuns of Nazareth House.

[citation needed] In 1898, John Crichton-Stuart, 3rd Marquess of Bute sold a large piece of land to Cardiff Council for the building of a new City Hall, imposing strict conditions regarding its purpose and where development could take place.

As a result, City Hall was built as far south in the purchased block of land as possible, and the residual area to its north used for civic, cultural and educational purposes only.

The land purchased by the council to the north of the city hall now houses: Maindy Pool was a clay pit that had gradually filled with water.

In 1948 the building of Maindy Stadium began on the same site, completed in 1951, which held cycling races in the 1958 British Empire and Commonwealth Games.

The area of Cathays, given its proximity to most of Cardiff University's teaching sites and the University Hospital of Wales, has seen a dramatic fall in owner-occupation, with a high proportion of houses in multiple occupation (HMOs) which are let through private landlords and letting agencies to the large student population.

[citation needed] The buy-to-let market has deterred young couples, families and first-time buyers from setting up home in the area.