Beginning in 1911 Parc Cefn Onn was laid out by Ernest Prosser, General Manager of the Taff Vale, Cardiff, and Rhymney Railway Companies. His intention was to create a woodland estate and house on the land then known as The Dingle. He built a summer house there for his son Cecil to convalesce from tuberculosis. Below the summer house was a pool used for bathing, and a small circular hut which served as a changing room. This was built from railway sleepers and it had a conical thatched roof.
Prosser abandoned his plans to build a house at The Dingle when his son died in 1922, but he continued to maintain the grounds until his own death in 1933. The estate was then inherited by a nephew, Donald S. Prosser, who sold it to the Cardiff Council in 1944 for £7,500. Prosser's head gardener, Tom Jenkins, alerted members of the Council to the opportunity to purchase the estate.
William Nelmes, Cardiff's Director of Parks, described how Parc Cefn Onn came to be acquired: "Local Authorities are often blamed for the protracted way in which they conduct their business and probably with some justification. In the case of the Parc Cefn On acquisition, however, very prompt action was taken : On a certain Saturday, in 1944, news was received that the property was for sale and the next day it was inspected by several members of the Council ; on the Monday a deposit was paid by the Chairman of the Estates Committee and on the Tuesday a meeting was specially convened to approve the purchase of the property by the Corporation."
The purchase was formally agreed on 21st August 1944 and the name Parc Cefn On was adopted the following month. Prosser's estate forms the northerly half of the present day park, as soon after purchasing the Dingle the Council acquired and incorporated the land to the south.
Tom Jenkins retained his position as head gardener and additionally assumed responsibility for the new southerly part of the park, where planting commenced in 1953. Parc Cefn Onn developed into a site of national horticultural importance, attracting many visitors especially in the rhododendron season. A description of the park and its trees, shrubs and plants appeared in the Gardeners' Chronicle in 1966. The present day Parc Cefn Onn still contains some rare and important native and exotic trees, while the streams, ponds, woodlands and other planting provide varied habitats for wildlife.
Parc Cefn Onn quickly became popular with visitors, such that public transport was improved, including a dedicated railway station, Cefn Onn Halt. In 1949 the Parks Committee approved plans to acquire a small plot of land south of the park to provide access from Lisvane Road and a site for a car park, but this work was delayed by legal issues. The construction of the new entrance was not carried out until 1952.
The original car park was considerably larger and extended further north than the existing one. It included a small building at its north end, providing toilets and a mess-room for park keepers. In the early 1980s this building was demolished and the car park and route into the park excavated to make way for the new Castleton to Coryton stretch of the M4 motorway. Following completion of the new section of motorway the Council accepted an offer of 340 square yards of land from British Rail to form a new car parking area.
The present day path leading from the car park now passes underneath the motorway and has to rise significantly to meet the original level of the park. The buildings adjacent to the existing car park - toilets, garage, mess-room and park ranger's bungalow - were all built after the motorway construction. Landscaping and planting of the motorway banks adjacent to the car park was carried out and funded by the Welsh Office.
Within the park there were other buildings for parks staff or public use. At the north end a picnic field was provided, described as follows in the 1970s: "Here are fine views of the City and the surrounding countryside and on a clear day you can see across the Bristol Channel. This field is a popular picnic spot as it has plenty of seats and there is space for children's games too. There is also a refreshment hut which is open during the summer months with toilets nearby."
In the 1970s and 1980s the stone-dust footpaths in the park were formed from gritstone obtained from Afan Argoed quarry at Neath. This was more suitable for the rhododendrons and azaleas because it is acidic. (Limestone was not used because it is alkaline.) Also at this time the area now known as the central walk between the upper and lower parts of the park, was the Azalea Walk. There were masses of Azaleas on both sides of the path which were top-dressed with grass cuttings from other parks and recreation grounds, such as Llandaff Fields, supplemented by sedge peat from Fisons in the Somerset Levels.
Sources of Information