Around a small church from the end of the 12th century, a larger construction was arranged in the 16th century and the curious facade (classified MH in 1911) presents today, under a single gable, a beautiful composition of Romanesque flowers and on the left, attached to it, an elegant Renaissance ensemble.
On the north side, a simple bell tower of the original church at its base, rebuilt in the last century in its upper parts, balances the whole. It is square, without style, covered with a slate pyramid, and has retained a few loophole openings. 3 of its arched windows each house a bell.
A semi-circular arched gate with three covings and 2 blind bays with only one, furnish the ground floor.
Above, without separation, runs a gallery of 5 arches supported on double columns. Bulky capitals, cords, bands very worked and in strong relief, indicate a novel of the end of time.
On the large coving develops a representation, with 6 "knights", of the fight of the Virtues and the Vices. On the intermediate arch, birds, monsters and human beings are tangled in vegetal arabesques. The sculptures of the capitals, abacus included, extend over the eardrums of the false doors and form a wide band.
In the Renaissance part on the right, the artist has arranged above a low door and around a large scallop shell, a very beautiful crowning with scrolls, garlands and fleurons.
Next to it a corner buttress shows another shell in a pediment.
The North wall, which has been modified many times, has however retained a large pointed arch towards its middle and a second one a little more towards the East. Old buildings, Benedictine ones say, existed there.
Remains of arches and Romanesque openings stand side by side with ogival windows. The eastern wall of the chevet, largely rebuilt, still shows 2 semicircular arches with ringed columns, nail-head cords and remains of an arcade similar to that which once adorned the north side of this same chevet. Although Romanesque, it therefore seems to have been rectangular from its origin.
To the left opens a large window whose central arch is polylobed. This provision is quite rare in Saintonge. The south wall, supported by numerous buttresses, one of which, the first to the west, is decorated with an escutcheon carried by two angels, is pierced with large third-point windows.
The square bell tower, without style, covered with a slate pyramid, has retained a few loopholes. 3 of its arched windows each house a bell.
The interior, refurbished two centuries ago, comprises 2 naves separated by square pillars. The one on the left, the old one, which has 5 bays, has its ogival vaulted apse on multiple ribs which are lost on the columns after having drawn diamonds adorned with hanging keys.
In these lozenges, letters forming a difficult to read inscription, a real rebus with a grid, indicate that this work was made in 1538.
Despite its name based on the idea of "fountain" this town which was formerly called Saint-Martin-de-Fontaine, has no fountains, but wells. The shallow one, very close to the church, was perhaps even less deep in the past and was undoubtedly the fountain which gave its name to the parish.
The church of Fontaine-d'Ozillac is patronized by Saint Martin.