The church sits at the centre of the col which gives Ganarew its name (from old Welsh: <em>Genau rhiw</em> translates as ‘Pass of the hill – situated between two hills’). The views out over the Little Doward hill and down towards Monmouth are spectacular.

It is not known when the ancient church was first established in Ganarew. It is possible that formal Christian worship took place during the residence of Vortigern (the last roman ruler of Britain circa 410) in what is now the parish of Ganarew. The earliest known dedication appears to have been to St Gwynnog (as recorded by Gildas d.570AD, first historian of the Celts). At some time prior to 1186AD the dedication was changed to St Thomas when it was recorded as being ‘the Chapel of St Thomas at Gueneru’ and attached to the Priory of Monmouth. A further record states that it was still so attached in 1292. The list of Rectors of Ganarew starts in 1294.

The current church building was built in place of a very much older church which had “<em>become much dilapidated</em>” and demolished in 1848. A drawing of this church hangs by the door in the present church. The work was made possible through the generosity of Mrs Catherine Marriott of Sellarsbrook (nearby) who did so in memory of her husband Charles Marriott who had died in 1848.

It is apparent from the drawing of the ancient church that the walls of the present building are on the same ground plan. The present building was designed by Mr Pritchard of Llandaff in the ‘middle-pointed’ or ‘decorated’ style of architecture. It is built with local sandstone rubble, faced on the exterior and plastered interior and with Bath Stone utilised for the window mullions. This church was dedicated by the Bishop of Hereford (The Rt Rev Renn Dickson) on 25^th October 1849. The dedication at that time was to St Luke. At a subsequent date the church became known as St Swithin’s. A gallery at the West end was removed when the present organ was installed in 1905. The installation of electric lighting and heating was carried out in 1930 with Mrs Levett of Wyastone Leys bearing the cost.

The churchyard is encircled with a sandstone wall (gifted by Richard Blakemore MP at sometime prior to 1849 when the current church replaced the earlier saxon building). Adjacent to the southern perimeter is a piece of ground – “17 perches more or less” – gifted in 1942 by Sir Alfred Hickman Bt. A tythe barn at the south eastern extremity disappeared sometime between 1820 and 1849 when it seems that the current lych gate would have been built. There is another gated access by the west end of the church. Until 1820 the roadway accessing the fold to the NW passed between the church and the Manor House. The celtic cross or preaching cross could well pre-date the earlier church.

The Reredos: The fine stone reredos, beautifully carved, was erected as a memorial to those from the Parish who gave their lives in the Great War 1914-1919 with their names inscribed on a tablet nearby on the south wall. The memorial was designed by Messrs. Wippell & Co of Exeter. The three panels depict Christ between two angels. A tablet commemorating those who fell in the 1939-1945 war was appended to the Great War tablet and is appropriately inscribed.