St Gwenllwyfo's Church, Llanwenllwyfo

St Gwenllwyfo's Church is a nineteenth-century parish church near the village of Dulas, in the north-east of Anglesey, Wales. A Grade II* listed building, it is celebrated above all for an extraordinary treasure: its collection of fifteenth- and sixteenth-century Flemish stained glass, described by the Welsh heritage body Cadw as the second largest such collection in the world. An "impressively large" Victorian estate church, its needle spire rising over the trees, it remains in use for worship by the Church in Wales.

The church was built between 1854 and 1856 to replace a medieval predecessor, also dedicated to St Gwenllwyfo — a seventh-century woman saint about whom almost nothing is known. The old church had fallen into disrepair and grown too small for its congregation, and although many parishioners lived at Nebo in the north of the parish, it was decided to build the new church to the south-west, near the Llys Dulas estate, whose owners had long been connected with it. The largest donation towards the cost of £1,417 — some £936 — came from Gertrude, widow of William Hughes, 1st Baron Dinorben, whose family fortune had come from the great copper mines of Parys Mountain on Anglesey. Her daughter and heiress, Gwyn Gertrude Hughes, laid the foundation stone on 14 September 1854 with a silver trowel and ebony mallet, over a box containing a Bible, a prayer book and an example of every British coin minted that year. The congregation was addressed in both Welsh and English, the latter by the curate Morris Williams, better known by his bardic name "Nicander". Designed by Henry Kennedy, architect to the Diocese of Bangor, the church opened in 1856.

Built in the Gothic Revival style of rubble masonry with gritstone dressings and a slate roof, the church has a four-bay nave, a two-bay chancel raised above it, and a three-stage west tower crowned by a spire that one guide has called "disproportionately tall" — the work judged "one of Kennedy's better works". An eighteenth-century bell and the octagonal font were brought from the old church, while the pulpit, choir stalls and other furniture are Victorian.

The church's glory is its Flemish glass. In 1876 Gwyn Gertrude Hughes's husband, Sir Arundell Neave, donated twenty-seven panels of stained glass that he had inherited from his father, who had bought them from a Norwich merchant with trade links to Flanders. The glass had come from a monastery in Leuven, in the Flanders region of Belgium, and most of it dates from around 1522, though the oldest pieces are late fourteenth or early fifteenth century. The east window shows scenes of Christ's betrayal and crucifixion, the Adoration of the Magi and the Holy Family's return from Egypt, incorporating fragments from a chapel commemorating Pope Adrian VI — tutor to the Emperor Charles V, whose head appears in the window — together with musical angels. Other windows depict saints and scenes from the life of Christ, including a "very rare" image of Jesus wearing a straw hat after his resurrection. Other glass from the same monastery is now held by the Metropolitan Museum of Art in New York, the Victoria and Albert Museum in London and the Burrell Collection in Glasgow.

The church is rich in memorials to the families connected with Llys Dulas — the Hughes, Dinorben and Neave families. A fine brass plaque of 1609, brought from the old church, commemorates Marcelie Lloyd, an heiress of Llysdulas, showing her and her husband Richard Williams kneeling with their children. Three funerary hatchments hang in the nave for Lord Dinorben, his wife Gertrude and Sir Arundell Neave, while Gertrude and her daughter both lie in a vault beneath the chancel. A large slate tablet records the contributions made towards the building of the church, and a model of the church made entirely from matchsticks is kept in a glass case in the chancel.

Today St Gwenllwyfo's is one of four churches in the parish of Amlwch, in the Diocese of Bangor. From its building as a Victorian estate church for the owners of Llys Dulas, through its needle spire and its incomparable collection of Flemish glass, it remains one of the most remarkable and rewarding churches on Anglesey — a country church holding within it the medieval art of a vanished Belgian monastery.