The history of Saint-Algis, whose church of the same name is situated in a very picturesque location overlooking the Oise valley, began in the 7th century when six Irish nobles and devout Christians arrived in the Thiérache to evangelise the country. Among them was Aldalgis, who settled here on the banks of the Oise and died there on 6 June 670, having done his work.

In the 12th century, the community was renamed “Algis” in his honour. A church seems to have already existed at this time.

The fortification of the church probably took place in 1634; but on the massive keep – the only one of the Thiérache on which a date (in glazed bricks) can be seen – the second digit is missing: so it could also read 1534. Probably the later date, but it could also just commemorate a repair. It is at least as spectacular as the one at Prisces, which is always mentioned as a reference, but a little lower.

This monumental cube of bricks, which in addition to four mighty buttresses also has two slender cylindrical towers connected to the nave, has something of a fortress about it. In one of the two towers there is a staircase leading to the escape rooms with 7 to X 7 m internal dimensions on the upper floors of the keep.

Incidentally, it is probable that it had two other corner towers: in fact, there is a document dated 5 November 1639 in which a “maître escalion” from Vervins, Pierre Mouze, undertook towards the inhabitants of the commune to re-clad “the great tower and four towers on each side” of the church of St-Algis.

The nave and the choir form a rectangle and are also built of brick. On one side of the nave is the date 1685, on the other 1687, probably indicating restorations. In the 19th century, the head of the church was in poor condition, so it was demolished and replaced by a flat wall.

Inside, the church has a wonderful atmosphere, no doubt due to the largely unplastered walls. Unusually, there is a wood-burning stove in the nave, although it is recent. The old fireplace in the keep can still be seen, but is no longer in use.

Open from 1 May to 30 June every Saturday and Sunday from 9 am to 6 pm and every day from July to September from 9 am to 6 pm.