Ynysangharad Park has its origins in the estate grounds of Ynysangharad House, the nineteenth-century home of the resident director of the Brown Lenox Chainworks, Gordon Lenox. The formation of Pontypridd Cricket Club in 1870 and the provision of a good-quality wicket on the Ynysangharad fields in 1873 has given the site a long association with sport in the town. In later years, the sporting facilities of Ynysangharad Park were home to Pontypridd Football Club (The Dragons) and Pontypridd Rugby Football Club and continues to be the home ground of the cricket club. In the summer of 1926, the cricket ground hosted First-Class County Cricket for the first time (the first ground outside of Cardiff and Swansea to do so in Wales).

In the early years of the twentieth century, Pontypridd Urban District Council endeavoured to purchase part of the Ynysangharad Fields in order to lay out a large municipal park. The original plans, dated 1909, identify sporting activity as the major purpose of this new park and the traditional Victorian features such as a bandstand and well-planeted promenades and pathways kept to a minimum. With the outbreak of the First World War in 1914, these plans were put on hold and negotiations with the Llanover Estate (which owned much of the land) halted.

After the war ended in 1918, councillors turned their attention once again to the provision of a public park on the Ynysangharad site. They were not alone. A committee had been formed by local townspeople to raise public funds for laying out the park as the town's war memorial. These two schemes continued in tandem until the creation of the Miners' Welfare Fund in 1920 (as per the Mining Industry Act of that year). The Miners' Welfare Fund provided large sums of money to the council thereby permitting the purchase and layout of the park and, through the influence of the memorial committee, its designation as the town's war memorial.

The park was officially opened in the summer of 1923 by Viscount Allenby, the commander of the Egyptian Expeditionary Force during the First World War. At the time of opening the park included several of the features that survive today: the tennis courts and cricket ground, football field, bandstand and ornamental features such as flowerbeds and the sunken garden. Over the course of the next few years, golf links were added (on the suggestion of D. L. Davies, the chair of the parks committee and later local MP) and the lido and paddling pool. The lido (NPRN: 415104) itself opened in 1927 largely through assistance from the Miners' Welfare Fund.

Sources:
Pontypridd Urban District Council, Minute Books (held at Glamorgan Archives)
Pontypridd Observer
Pontypridd Chronicle
Pontypridd District Herald
Glamorgan Free Press

Daryl Leeworthy, RCAHMW, 15 June 2012