Commana lies among the rounded ridges and wet valleys of the Monts d’Arrée, where the built landscape carries as much history as the moors. The town is a rural community in the Armorique Regional Natural Park and the Pays de Landivisiau intercommunal area. Its character comes from a close-knit centre, scattered hamlets and working traces of several eras: a richly carved parish enclosure, a prehistoric burial passage, slate workings, a former mill village and the wetlands around the Mougau and Drennec.
A population for the whole commune
INSEE’s 2023 census reference gives Commana a municipal population of 983, with a density of 24.6 residents per square kilometre. This is the figure for the entire commune, not just the village centre. It also corrects older municipal pages that still show 1,038. INSEE recorded 26 employer establishments at the end of 2024; agriculture, forestry and fishing made up 30.8% of that small group, while commerce, transport and services made up 34.6%. The figures describe employer establishments, not every independent worker or activity, but they fit a landscape where farming remains visible alongside local services and small businesses.
Read the parish close as a dated ensemble
At the centre, Saint-Derrien stands inside an enclos paroissial: church, enclosing wall, cemetery, monumental arch, entrance, ossuary and two calvaries form one architectural setting. The Ministry of Culture’s inventory records an earlier church in archival evidence, followed by substantial rebuilding from 1592 and major works through the seventeenth century. Inscriptions and dates across the ensemble include 1592, 1645, 1650, 1653, 1677, 1686–1687 and 1701. The south porch, sculpted stonework and freestanding crosses reward a slow walk around the enclosure; the place is best understood as the shared focus of a parish, rather than as a single church façade.
Prehistory, mills and slate
Near Mougau-Bihan, the covered passage known as Al Lia Vaen is a 14-metre collective tomb built between 3000 and 2000 BCE. Its granite supports carry stylised engravings. Archaeology identifies a burial monument; local tales of giants and the night-roaming korrigans called Bugel Noz belong to folklore, not to the documented account of its purpose.
Kerouat offers another time layer: the hamlet developed between 1610 and 1910 around watermills, hydraulic works, bread ovens and a house built in 1831. The Department acquired the site in 1971 for the regional park’s ecomuseum. The ecomuseum’s current visitor information says the Kerouat site is closed for works; its exceptional September opening has passed, so check directly for a reopening date before travelling. Slate was also a local industry. The regional heritage inventory traces quarries at Mougau, Kerohant and Restancaroff in records from the 1850s onward; Kerohant continued until about 2006. These are industrial remains, not an invitation to enter abandoned excavations.
Walk gently through water and moor
The Mougau bog interpretive trail uses boardwalks to cross a fragile wetland, while the Drennec reservoir offers a lakeside circuit and seasonal recreation. The municipality lists around fifteen walking itineraries with variants. Tourisme Bretagne describes the Blue Stone trail as a 16-kilometre walk of about four hours, beginning at the church square and reaching Lake Brennilis. The bog trail is seasonal, and the local site warns that water levels can flood paths. Check current maps, closures and weather before setting out, keep to marked paths and avoid trampling bog vegetation.
Useful stops and current access
The town’s official directory lists a general food shop with bread, a restaurant beside the lake, a post-office counter and local schools, including the bilingual Diwan school. Business hours and facilities can change; confirm them before relying on a meal or service. Commana is best visited as a landscape of linked stories: begin at the parish close, follow a marked route toward Mougau or the water, and treat the mills as a future visit until their official reopening is announced. Trail timetables, opening dates and lake services should always be checked with the responsible operator.
