Lieu-dit · Romanèche-Thorins
Les Prés Dessous
Les Prés Dessous is a lieu-dit in Romanèche-Thorins, Beaujolais in Saône-et-Loire, whose largest tier is regional.
3.12 ha
delimited
240 m
elevation
11.3 h
sun at harvest
Open on the mapWith the boundary, the plots, the sun through the year and the bedrock.
In figures
| Level | Regionalinao-aoc-viticoles-bulk (c. 4 September 2026) |
|---|---|
| Village | Romanèche-Thorins |
| Region | Beaujolais in Saône-et-Loire |
| Delimited | 3.12 hainao-aoc-viticoles-bulk (c. 4 September 2026) · cadastre-etalab (4 September 2026) |
| Planted | 0.11 hacadastre-etalab (4 September 2026) · ign-bdtopo-vigne (5 September 2026) · ign-rpg-2024 (5 September 2026) |
| Parcels | 16 |
| Grape variety | pinot noir, gamay, césar also permitted: aligoté, chardonnay, gamay de bouze, gamay de chaudenay, melon, pinot blanc, pinot grisinao-cahiers-des-charges (7 September 2026) · dgddi-superficies-produits (7 September 2026) · franceagrimer-observatoire-viticulture (7 September 2026) |
| Organic | 0%agence-bio-cartobio (c. 5 September 2026) · agence-bio-operateurs (5 September 2026) |
Place in the village
Among the 16 named plots ranked regional in Romanèche-Thorins, from high to low:
Position
240 m
elevation
5.6%
gentle
E
east
mid-slope
even slope
| Elevation | 240 m 233 to 246 mign-rge-alti (5 September 2026) |
|---|---|
| Daytime temperature | −0.17 °C by day, relative to the village centre at 215 m, ± 0.08 °Cmeteo-france-quotidiennes (18 September 2026) · meteo-france-postes (6 September 2026) · meteo-france-lsh (6 September 2026) · ign-rge-alti (5 September 2026) |
| Slope | 5.6% 3.2°ign-rge-alti (5 September 2026) |
| Aspect | east 98°ign-rge-alti (5 September 2026) |
| On the slope | 33% mid slope, on an even plane, 1,035 m drains onto itign-rge-alti (5 September 2026) |
Bedrock
- 100%Porphyritic monzogranite and quartz monzonite, Carboniferous about 350–330 million years (Dinantien, inferred from the map, not radiometric)
In the glass. Tends towards fragrant, finely built wines with tannin that is supple rather than broad. In practice that picture comes at least as much from the shallow, poor soil and the exposure as from the rock itself.
Igneous rock that crystallised deep in the crust during the building of the Hercynian mountain chain, roughly 350 to 330 million years ago. Porphyritic means that centimetre-sized feldspar crystals sit in a finer groundmass, which gives the stone its mottled, pink to pale grey appearance. At the surface this rock weathers to a coarse-grained, crumbly sand known locally as gore or arène, with half-rotted rock beneath; the depth at which solid rock begins varies greatly, from a few decimetres to several metres.
For the vine. Lime-free and acid, so virtually no risk of chlorosis, but no lime buffer either. The arène is very free-draining and warms quickly, which favours early ripening, but holds little water, so the depth of the weathered layer determines whether the vineyard gets through a dry summer. On shallow, steep plots it dries out quickly; where weathering goes metres deep, the vine roots far down and the water supply is in fact remarkably regular.
Occurs in the granite knolls of the southern Mâconnais around Chasselas and Leynes. Which Beaujolais crus lie precisely on this unit cannot be established without a parcel map; the well-known pink granite of Fleurie and Moulin-à-Vent belongs to a younger massif.
BRGM geological map at 1:50,000. It tells vineyards apart, not plots within a vineyard. The link between rock and taste is indirect: soil depth, water and warmth do the work, and slope, vine age and the cellar do the rest. Units on that map: h1-2pγ3.
brgm-bdcharm50 (4 September 2026)Sun and horizon
07:31
above the hill
18:48
behind the hill
11.3 h
sun at harvest
0.6 h
lost to the hill
Grey: sun up, behind the hill or its own slope.
Around harvest the sun rises here at 07:31 above the hill and disappears at 18:48 behind the hill: 11.3 hours of direct sun on a clear day. The ridge reaches 9.4° above the horizon to the west.
| Irradiation | ±0.0% versus flat land 1,082 kWh/m² from April to October, 40% of it diffuseunder the average cloudiness of 2005 to 2023 (PVGIS-SARAH3, EU JRC); direct, diffuse and reflected light togetherign-rge-alti (5 September 2026) · ign-lidarhd-mnh (6 September 2026) · ign-bdforet-v2 (5 September 2026) · jrc-pvgis-sarah3 (10 September 2026) |
|---|---|
| Open sky | 99.6% of the sky the slope itself sees; the surrounding relief blocks the restign-rge-alti (5 September 2026) · ign-lidarhd-mnh (6 September 2026) · ign-bdforet-v2 (5 September 2026) |
Three reference days, the caveat
| rise | set | sun | day | |
|---|---|---|---|---|
| 21 June | 05:53 | 20:39 | 14.8 h | 15.8 h |
| 20 September | 07:31 | 18:48 | 11.3 h | 12.3 h |
| 21 December | 08:30 | 16:06 | 7.6 h | 8.6 h |
Computed from the IGN elevation model at 5 m: horizon in 36 directions up to six kilometres, sun position per minute, angle of incidence on the mean slope. Clear sky, with the tree canopy from the IGN forest inventory as a raised horizon (15 m closed forest, 5 m heath, trees within 60 m ignored), 21% of the far field is forest (BD Forêt), no buildings.
Air and cold
13 m
above the lowest point
drains away
cold air
a combe
23.6 ha flows past
| Cold air | 13 m above the hollow, cold air drains awayign-rge-alti (5 September 2026) |
|---|---|
| Cold air passing through | 23.6 ha a combe, mean over the polygon 1.69 haign-rge-alti (5 September 2026) |
Planting
ESE-WNW
down the slope
1.01 m
between the rows
100%
vineyard in 1950
| Rows | ESE-WNW (111°) down the slope (13°), every 1.01 m, all rows parallelmeasured over 0.1 of 0.1 ha plantedign-bdortho (5 September 2026) |
|---|---|
| Vineyard in 1950 | 100% abandoned since: 1.09 ha, rows then ran 83° differentlyassessed over 1.2 ha on the 1950-1965 aerial photographign-photos-historiques-1950-1965 (6 September 2026) |
Climate over time
station MACON, 219 m, 12.3 km away
growing season, April to October: 1951-1980: 15.4 °C, 1991-2020: 17.1 °C
Huglin index: 1951-1980: 1,718, 1991-2020: 2,022
last spring frost: 1951-1980: day 96, 1991-2020: day 85
series homogenised through 2022
The name
- pre
- meadow. Ground that carried grass before the vines came, or lay beside them. Vegetation · Gérard Taverdet, Noms de lieux de Bourgogne (2007)
- dessous
- below, lower than the thing named. Shape and position · Terroirium, Eigen telling over de namen in deze atlas (2026)
This is about the words, not about this plot: the same name can have arisen differently elsewhere.
Who owns land here
1.48 ha of 3.12 ha delimited is registered to a legal entity
- CHATEAU DU MOULIN A VENT40%
- ZEPHYR7%
- S I V U POUR L'ASSAINISSEMENT COLLECTIF DES COMMUNES DE LA C<1%
- private individuals or unknown53%
- 1.26 ha CHATEAU DU MOULIN A VENT SARL · wine business · organic
- 0.21 ha ZEPHYR SARL · other
Private individuals or unknown: 1.64 ha.
Share of the delimited hectares. Only legal entities are public in France; everything else stays unnamed. From the public register of legal entities (DGFiP), as of 1 January 2025. The owner is not always the one who works the vineyard: tenancy is common.
Nearby lieux-dits
- Les Hantes Village · 100 m
- Les Prés de la Fontaine Regional · 150 m
- La Grande Charriere Village · 250 m
- Les Gros Vosges Village · 250 m
- Les Thorins Village · 300 m
- Le Moulin a Vent Village · 300 m
- La Roche Village · 400 m
- Le Petit Morier Village · 500 m
In the same village, measured between label points. That does not say which ones border each other; the map shows that.
Where each figure comes from
- Classification
- The INAO delimitation per denomination, cut against the cadastral parcel. Only the INAO's own plans are legally binding; this map is informational.
- Area
- Computed on the sphere from longitude and latitude (turf.area), not in Lambert-93. For an appellation this is the union of the INAO polygons across commune boundaries, measured on the unclosed geometry; the fifteen metres used to close the outline for the map are not counted. For a climat it is the union of the cadastral lieu-dit polygons with that name.
- Planted
- Parcel area times vineyard cover, where cover comes from the IGN vegetation layer supplemented by the agricultural declaration. Checked against the customs harvest declarations: median deviation 5.1 per cent over a hundred appellations.
- Elevation
- Mean of the elevation-model cells whose centre falls inside the polygon, on a 5 m grid.
- Slope
- Per-cell slope from the elevation model using Horn's method, then averaged over the cells in the polygon.
- Aspect
- Vector mean of the per-cell aspect. A plain average would turn north-east and north-west into south.
- Sun at harvest
- Hours of direct sun on 20 September under a clear sky, with the horizon in 36 directions out to six kilometres and the height of woods and buildings on top of it. Canopy height is measured where LiDAR HD covers the area and estimated from BD Forêt where it does not; the panel states which of the two was used.
- Grape variety by appellation
- Per appellation and colour the permitted varieties from the approved cahier des charges; per appellation and tier the declared hectares of white and red from the customs harvest declaration (product codes). One colour permitted: the main variety of that colour. Two colours: from 85 percent of the hectares that colour applies, in between it is called mixed. Champagne: the dominant variety from the planted hectares per variety per commune from FranceAgriMer. Per polygon the dominant variety of its parts by area. Derived, not measured: the variety per plot exists only in the customs vineyard register, which is not public. In a two-colour appellation a single plot may carry the other variety. Customs withhold small appellations (statistical secrecy), in which case the split is missing.
- Bedrock
- The geological unit covering the largest share of the polygon, from the 1:50,000 geological map. At 1:50,000 the map separates one climat from another, but not what varies inside a climat.
- Organic
- Share of the area certified organic or in conversion, from the CartoBio plot register.