It sometimes happens that you discover old vestiges on your land when you do work. What you need to know when faced with a discovery.
A potentially archaeological site
If you think that the land you are coming or about to acquire may contain historic vestiges, the first thing to do is to consult the national archaeological map with the regional archeology services of the Regional Directorate for Cultural Affairs (DRAC), or the municipal archaeological zoning map in the town hall of the municipality concerned. Generally, these maps are integrated into the Local Urban Plan (PLU) of the city. When a building permit is deposited in an archaeological area, the prefect is sometimes systematically seized.
Who owns the remains found on my property?
At the time of construction, if you find archaeological remains such as ancient walls or mosaic remains, or objects such as glassware or coins, you become what is called "the inventor" . But if it is the building company in charge of the works that makes this discovery, it is it the inventor. However, the discoveries then belong both to this inventor and to yourself, after having declared them together at the town hall.
What to do after discovering remains?
First of all, you stop the works and go to inform the town hall of your discovery. The Regional Archeology Service (SRA) will then come to your property to judge the archaeological interest of what you have found. He then decides on the measures to take to possibly save the site or continue his exploration. If you have made a major discovery, which is rare, let's face it, the regional prefect may require you to suspend your work for several months.
Who keeps the remains?
For building remains, the Ministry of Culture can impose definitive measures on you in order to preserve them. For objects, they may be the subject of a scientific study for several years (five years maximum). You will then recover and own them. However, the State has the right to recover them, subject to the payment of an indemnity fixed between you or with the help of an expert.
The case of preventive archeology
Before the start of a large construction or development site, it happens that the regional prefect prescribes an archaeological diagnosis at INRAP, in order to avoid that the site may be interrupted during the works. If the field surveys carried out do not reveal any interesting historical trace, construction (of a suburban area, for example) can start. Otherwise, the State may impose excavations and modify the project of the promoter or developer. The remains can then be integrated into the project.