ClasséAbbey · protected 1862Église de l'ancienne abbaye, actuellement basilique Notre-Dame-de-Bonne-GardePhoto: self · CC BY-SA 3.0 · Wikimedia Commons
Photo: Naudinsylvain · CC BY-SA 3.03historic monuments
History of Longpont-sur-Orge · Monuments historiques
3 historic monuments and a protected historic area since 2019
The Culture ministry lists 3 historic monuments in Longpont-sur-Orge: 1 classé (France’s highest heritage protection) and 2 inscrit (the second level). The oldest date from the 12th century. Since 1862, Longpont-sur-Orge has had a listed monument.
Monuments historiques
3
Classé
1
the highest protection
Inscrit
2
the second level
Oldest part
12th c.
of any listed monument
Homes before 1919
3.7%
median compared town 7.4%
In pictures
Monuments of Longpont-sur-Orge in pictures
Tap a photo to step through them full screen.
Église de l'ancienne abbaye, actuellement basilique Notre-Dame-de-Bonne-GardeClassé
Réseau hydraulique de la source de LormoyInscritPhotos from Wikimedia Commons, copied to our own server, each credited to its photographer with its license; names open the monument’s page.
Protected area
Longpont-sur-Orge has had a protected historic area since 2019
Sites patrimoniaux remarquables on the Culture ministry’s list, with the plan in force.
| Area | Created as | Plan in force |
|---|---|---|
| SPR11-40 | AVAP April 3, 2019 | AVAP (heritage area rules) April 3, 2019 |
A site patrimonial remarquable protects a whole area rather than one building: inside it, building work follows the area’s own plan and needs the agreement of the architecte des Bâtiments de France.
The list gives no boundaries, so the map can’t show the area.
Map
Where Longpont-sur-Orge’s monuments stand
Every monument with a point on the ministry’s list; the larger, darker dots are classé.
ClasséInscrit
Tap a dot to open the monument’s page: its record, photo and the monuments around it.
3 monuments by protection
1 Classé2 Inscrit
Classé is the higher protection: any work on the building needs the State’s permission. Work on an inscrit building must be declared to the State in advance. Around both, building work in sight of the monument (usually within 500 m) needs the agreement of the architecte des Bâtiments de France.
Points as the ministry gives them: a monument spread over several plots has one point.
Classé
One classé monument in Longpont-sur-Orge
Classé is France’s highest protection for a building, held by about a third of the monuments on the list. Each card opens the monument’s page.
Inscrit
2 inscrit monuments in Longpont-sur-Orge
Inscrit is the second level of protection: the building is worth keeping, and any work on it must be declared.
InscritEngineering work · protected 2002Réseau hydraulique de la source de LormoyPhoto: Grefeuille · CC BY-SA 4.0 · Wikimedia Commons
Farm building · protected 2016Ensemble agricole monastique
Age of homes
3.7% of homes in Longpont-sur-Orge were built before 1919
Main homes by when they were finished, beside the median compared French town (the tick).
3.7%
Before 1919
1.9%
1919–45
11%
1946–70
38%
1971–90
26%
1991–2005
19%
2006 on
Longpont-sur-OrgeMedian compared French town
3.7% of its main homes were built before 1919; the median compared French town has 7.4%. More of them were finished between 1971 and 1990 than in any other period (38%).
INSEE, census 2023: main homes (résidences principales) only; second homes and empty homes aren’t dated.
Towns its size
Longpont-sur-Orge has the 8th most monuments of 41 towns its size
Compared French towns of 6,400 to 6,500 residents, by historic monuments.
Longpont-sur-Orge3
The median town of these has 1. 10 of the 41 have none.
Neighbors
Historic monuments in the towns around Longpont-sur-Orge
| Town | Residents | Monuments | Classé | Protected area |
|---|---|---|---|---|
| Longpont-sur-Orge | 6,482 | 3 | 1 | Yes |
| Montlhéry | 9,772 | 5 | 1 | — |
| Villiers-sur-Orge | 4,545 | 0 | 0 | — |
| La Ville-du-Bois | 8,161 | 0 | 0 | — |
| Saint-Michel-sur-Orge | 21,776 | 0 | 0 | — |
| Linas | 7,987 | 1 | 1 | — |
| Ballainvilliers | 4,904 | 0 | 0 | — |
In brief
Longpont-sur-Orge in brief
The record in Longpont-sur-Orge starts with Église de l'ancienne abbaye, actuellement basilique Notre-Dame-de-Bonne-Garde, which dates from the 12th century. All told, the list holds 3 historic monuments, 1 of them classé, including Église de l'ancienne abbaye, actuellement basilique Notre-Dame-de-Bonne-Garde. In 2019 the Mission Patrimoine picked Église de l'ancienne abbaye, actuellement basilique Notre-Dame-de-Bonne-Garde as a monument in danger to save. Only 7 of the 41 towns nearest its size have more historic monuments.
Part of it has been a site patrimonial remarquable since 2019. Its homes are mostly newer: 3.7% were built before 1919, against 7.4% in the median compared French town. Beyond that, the list grew between 1862 and 2016.
How to read these numbers
What this data can and can’t tell you
- Monuments historiques. France protects buildings at two levels. Classé, the higher (about a third of the list), means any work needs the State’s permission; inscrit means work must be declared to the State in advance. The Culture ministry’s Mérimée base lists every protected building, and this page counts them.
- Partly protected. Many entries protect part of a building only (its façades and roofs, a staircase, a painted room). Each counts as one monument, like a fully protected one.
- Where a monument is counted. In the commune named on its protection, moved to today’s commune where communes have since merged. A monument listed for several communes counts in each.
- Sites patrimoniaux remarquables. Since 2016 France’s protected historic areas (the former secteurs sauvegardés, ZPPAUP and AVAP) share one name. Inside one, building work follows the area’s plan and needs the agreement of the architecte des Bâtiments de France.
- What isn’t here. Protected objects (furniture, organs, paintings), old buildings with no protection, UNESCO World Heritage listings and labels such as “Plus Beaux Villages de France” aren’t on this list, so this page doesn’t count them.
- No History Grade yet. Everything on this page is described, not graded: France’s History Grade isn’t built yet.
Questions about the history of Longpont-sur-Orge
How many historic monuments are there in Longpont-sur-Orge?
The Culture ministry lists 3 historic monuments in Longpont-sur-Orge: 1 classé and 2 inscrit.
Which monuments in Longpont-sur-Orge are classé?
One: Église de l'ancienne abbaye, actuellement basilique Notre-Dame-de-Bonne-Garde.
Is Longpont-sur-Orge a protected historic area?
Yes: part of Longpont-sur-Orge has been a site patrimonial remarquable since 2019.
How old are the homes in Longpont-sur-Orge?
3.7% of its main homes were built before 1919 (median compared French town: 7.4%).
France has no History Grade yet: this page describes, it doesn’t grade.
Sources: Ministère de la Culture, Mérimée base on POP (immeubles protégés au titre des monuments historiques), October 2026 · Ministère de la Culture, sites patrimoniaux remarquables, October 2026 · INSEE, census 2023 (main homes by build period) · Wikimedia Commons and Wikidata (photos of the monuments, each with its own credit and license) · IGN Admin Express (boundaries) · Medians and percentiles: TownRatings, over compared French towns, updated November 4, 2026. Under the Licence Ouverte / Open Licence 2.0 (Etalab).
Contains public sector information under the Licence Ouverte / Open Licence 2.0 (Etalab): INSEE, DGFiP, the Interior Ministry’s statistics service (SSMSI), the Ministry of Education (DEPP), the Health Ministry’s statistics service (DREES) and the Housing Ministry (Carte des loyers). Commune boundaries: IGN Admin Express.