Fonmon Castle Watchtower

Fonmon Castle Watchtower

Fonmon Duckpond

Fonmon Duckpond


Fonmon Castle (Welsh: Castell Ffwl-y-mwn) is a fortified medieval castle near the village of Fonmon in the Vale of Glamorgan and a Grade I listed building. With its origins rooted in the 12th century it is today seen as a great architectural rarity, as it is one of few buildings that was drastically remodeled in the 18th century, but not Gothicized. The castle is believed to have remained under the ownership of just two families throughout its history; from Norman times the St Johns and from 1656 the descendants of Colonel Philip Jones.

The origins of Fonmon castle are poorly documented and most of its early history has been discovered through studying its architecture. A popular myth exists that the castle was built by Oliver St John of Fonmon, one of the Twelve Knights of Glamorgan who effected the Norman conquest of Glamorgan. It has since been shown that this was a legendary tale given credence by a "historic" recount in the 1560s by Sir Edward Stradling.

There is speculation that a defensive fortification made of timber was built on the site of Fonmon Castle soon after the Norman invasion of Wales, with stonework added around 1200. The thick walls to the left of the entrance are easily identifiable as 12th century in design, and shows the existence of a rectangular keep. This keep was relatively small in size, approximately 8 metres x 13 metres. In the 13th century a curtain wall was added to the east side of the keep leading towards a steep scarp. This was followed by a much larger L-shaped build to the south with a south-east tower added at the angle.

The east wall along the ravine edge has the castle's thickest walls, which is a curiosity as this would have been the most difficult side to attack. It is therefore believed that some other defensive structure may have existed to protect the more vulnerable south and west approaches. These early constructions are thought to have been undertaken by the St. John family, who were associated with the castle during the Middle Ages and continued as owners until 1656. It was not until the 16th century that the next major addition was made, a short north wing built over a barrel-vaulted semi-basement.

The castle survived being damage during the English Civil War, with the St. John family supporting the Parliamentarians, but shortly thereafter they fell into financial difficulties and the castle was sold to Colonel Philip Jones. It is believed that Jones then improved the rooms on the east range and added a double depth wing to the north side. Upon Jones' death the castle was passed down to his son Oliver who owned the castle from 1678 to 1685. It was Oliver's great-grandson, Robert Jones III, who was to make the next major redevelopment to the castle. He married Jane Seys, heiress to the Seys of Boverton and in 1762 they began the castle improvements, employing Thomas Paty of Bristol. The firm added render and made additions the battlements to give it more of an appearance of a castle.

The estate went into a period of decline in the 19th century and little work was done to the castle except for the addition of the entrance porch and the extension to the south wing in the period between 1840 and 1878. The castle passed by marriage to Sir Seymour Boothby of the Boothby baronets in 1917 and his grandson still lives there.

The castle is open to the public on Tuesday and Wednesday afternoons from April to September; access to the garden and grounds is free. It is also a wedding and events venue, hosting the Vale of Glamorgan Agricultural Show since 1998 and the St David's Polo Club.


Fonmon Castle is situated in extensive gardens and is constructed of local sourced stone, primarily limestone and blue lias rubble. There is one arched internal doorway which appears to be Sutton stone; but are covered in grey render which disguises much of the stonework. The roofs are of mixed slates with lead gutters and dressings. The main building is of two and three storeys and castellated almost throughout. Apart from the south east corner tower, which is slightly higher, the walls are largely uniform in height.

In the grounds, to the south west of the house, there is an 18th-century stable which incorporates a late medieval barn. The south and east walls of the stable are castellated to impress those approaching from the south. The stable has a fine polygonal stone chimney, which is a rare surviving medieval find, taken from East Orchard Farm, St Athan. The Joneses acquired East Orchard Farm in 1756, but abandoned the building after stripping it of its dressed stonework.

Further south is a battlemented watch tower of either 17th or 18th century design, thought to have been modeled on the one found at St Donat. It is believed the watch tower was constructed in two builds, and may have been founded on original ruined medieval stonework. Although it appears to be of 16th century design, it does not appear on the estate plan of 1622, but does appear on the plans of 1770 giving a wide window for its construction date. Due to its time scale and features, it is assumed to have been constructed during the medievalizing improvements carried out by Robert Jones III. It is constructed of local roughly coursed limestone rubble, which has been lime-plastered. It was given Grade II* listed building status in 1952, with the reason given as "an interesting example of a C16 and late C18 look-out tower and for its group value within the gardens of Fonmon Castle".

Interior. Notable features include the combined grand drawing room and library, designed by Thomas Stocking. Described by Newman as the "glory of Fonmon", the library, running east to west is lit by two Venetian windows, a stone one to the west wall and a sashed timber oriel window to the east. The room is divided into three sections, the largest central, with square end bays with segmental arches. There are trophies of the chase in the spandrels of the arches and arabesques and wreaths adorn the flat of the ceiling with an Apollo head in a sunburst at its centre.

On your tour you will hear of the different ways of life and see the different styles of living which have emerged and overlapped as the centuries have passed. See the small stone ceiling from the 13th century; portraits and paintings dating from the 16th century onward; the 17th century Old Kitchen; the 18thcentury gilt; plasterwork Library and mementoes of the 20th.

Before or after your tour, enjoy a stroll around the gardens to see trees from the 19th century, the walled gardens and watch tower. They also welcome researchers and educational groups at almost any time but these need to be arranged prior to the visit.

The Hall. The Hall is a two story space created from four rooms of the early castle. The two ceilings have rococo plasterwork and light is provided by a beautiful Georgian crystal chandelier. The walls are lined with paintings, mostly portraits of family members such as of Colonel Philip and his descendants including Robert Jones III painted by Sir Joshua Reynolds. The Drawing Room. This is a rectangular, south facing room, again formed out of two rooms of the early castle. It has a fine rococo ceiling in the smaller of the two original rooms and a plain ceiling in the other. The Drawing Room was once used as a meeting room by John and Charles Wesley. Hanging in this room are portraits of some of Sir Brooke’s ancestors, the first of whom is reputed to have come from Denmark as long ago as 870 AD.

The Library. Robert Jones III great creation was the beautiful Library. This is the principal room of the house. It was formed in 1760 from two of the oldest rooms in the castle and is sumptuously decorated with rococo plasterwork and gilded mirrors and fireplaces. It houses the book collections of both the Jones and Boothby families that contains rare and aged volumes dating back to the 15th Century. The Old Kitchen. When the kitchen was built by Colonel Philip in the 1650’s it was described as “ye largeste kitchen of ye inhabited castle of ye kingedom” and was used as a working kitchen for almost 300 years. The room is dominated by the huge dresser over 5m long on which is displayed some of the family pewter. Old kitchen fittings and fixtures are evident everywhere and a small collection of weapons hangs on one frame. There are many other ancient and interesting features to see during a visit to Fonmon.

Fonmon Castle was originally built around 1180, They presume that some form of garden was started from that time to help supplement the diet of the owners, their families and staff. Unfortunately however, no early records remain of anything close in to the main building. Further out from the Castle, it is clear that the orchard was more extensive than it is today and beyond the paddocks for the domestic animals was an area for ‘harvesting’ rabbits, then a popular food stuff. Earlier called the Coneygrye, this area now survives, as do the rabbits, as a field named the Cernacre.

The castle itself had a wall curtilage extending to some acres which is supposed to have been for the protecting of the animals and possessions of the local villagers during times of what was politely called ‘unrest’ – this normally meant the local Welsh rebelling against their Norman French rulers. Today this forms the primary boundary of the gardens although it is not always obvious where the original edges ran, owing to 17th, 18th and 19th century alterations. The prime changes came in the 18th century when the castle itself was remodelled by Robert Jones III the great, great, great, great, great grandfather of the present owner. Robert III’s changes between 1760 – 1790 left the gardens much as they are today, with the one major exception being that the approach drive was moved around 1870 from the south to the west.

Today a visitor comes over the bridge crossing the modern Cardiff airport bypass to find firstly an area of large trees acting as a protective screen from the prevailing westerly winds. The trees are interspersed with shrubs to provide tempting glimpses of the castle, stables and gardens to the east. After parking, the route to the Castle passes by the old well head and through the 1870 gap in the walls. The driveway to the front door bisects the gardens into North and South. On the South side, three herbaceous borders run around the stable block, itself an 18th c conversion from of the old tithe barn. Various large shrubs are interspaced with roses and climbers running up the walls. Beyond is a lightly planted area mostly of specimen trees, which used to be the old grass tennis court.

Then to the South East lies the Watch Tower with the remains of the old walls flanking it and a small grass border to the north. Further north lies the Dell garden which holds typical shade and damp loving plants such as gunnera, a collection of ferns, bamboo and bulbs. A pale Metasequoia glyptostroides contrasts with the enormous copper beech overhanging from the upper terrace. The top of the dell is planted with small borders backed with climbing roses and leads round to the copper beech tree. This exceptional specimen is thought to have been planted in about 1815 and effectively sits in a giant “pot” comprising of walls on three sides and the edge of the limestone underlying the lawns on the fourth. From the copper beech, a border leads back to the south front of the castle, again planted with herbaceous and shrub planting.

The castle itself is partially covered by Virginia Creeper planted before 1900 and making a spectacular crimson sheet in autumn. Just to the west of the south wing is a century-old Garrya elliptica, which offers fine catkins up to 30cms long in early spring. The north lawn is flanked by further borders and a small shrubbery. One border is largely given over to hardy fuchsias, Clara, Lady Boothby – Sir Brooke’s grandmother being the founder President of the British Fuchsia Society (1938). Through a gate in the wall backing the fuchsia border is an intimate small walled garden with a wide variety of shrubs and an old sundial. From the NW corner of this garden a door leads through to the Scented Garden with its small summerhouse and another sundial of a different style.

From the scented garden, another door leads into the larger Walled Garden with a Herb Garden on the right behind a fine beech hedge. This garden is mostly given over to fruit and vegetable production and was once believed to be the largest fully functioning kitchen garden in Glamorgan. A small iron gate in the north wall leads out to the orchard area beyond and a level track can be followed past the bees, through the beech grove and back across the Cernacre and the Forty Acre fields (the latter once know as the ‘Lord’s Demesne’).


The Castle is available to visit throughout the year, but times and conditions for visiting vary. From April to September inclusive, during their Public Opening season, anyone can visit Fonmon on a Tuesday or a Wednesday afternoon and they welcome casual visitors. There are guided tours of the castle itself on Tuesdays and Wednesdays at 2pm, 3pm and 4pm. The tour lasts approximately 45 minutes and there is a charge of £6 per person for all over the age of 14. The gardens and grounds are open free of charge from 12 noon to 5pm (last entrance at 4pm). At all other times, an advance booking is necessary, arrangements for visits booked in advance are as for Group Tours below.

There are no refreshment services available unless booked in advance as part of the Group Tour arrangements. Assistance dogs are the only dogs allowed in the Castle, Gardens or Grounds. Almost all the areas of the grounds and castle are accessible by wheelchair with the Dell garden requiring some skilled ‘driving’ (although it can be seen more safely from above). Other parts require crossing grass which may be a problem in wet weather.

Group Tours. Visits and Tours without refreshments can be booked in advance (subject to availability) at any time throughout the year for groups of 12 or more. For visits by groups of 20 or more we are happy to provide refreshments, with or without a tour. These can range from morning coffee, light lunch, afternoon tea, or a full evening meal all home cooked and taken in one of the sumptuous Castle rooms – our Tour & Tea option being especially popular. To book a Group Tour , or for any further information on Public Opening, please contact their office.


Location : Fonmon Castle, Fonmon, Barry, Vale of Glamorgan CF62 3ZN

Transport : Barry (National Rail) then bus (303). Bus Routes : 303, 905 and X91 stop nearly 1 mile.

Opening Times Castle: see above

Opening Times Gardens: Daily, 12:00 to 17:00

Tickets Castle: £6.00 per person 14+;  Children under 14 Free

Tickets Gardens: Free

Tel : 01446 710206