Yes, France restricts anchoring in parts of the Mediterranean to protect Posidonia seagrass, a protected native meadow grass that covers large areas of the seabed off the French Riviera and Corsica. In practice, this affects exactly where the anchor touches bottom inside a bay, not whether your yacht visits that bay. Our captains check the current anchoring charts before every charter, so this is a planning detail we handle before you arrive, not something that changes your route on the day.
Coves like these off Porquerolles are exactly the kind of protected water where the anchoring rules apply most.
Quick Take
- What’s restricted: dropping anchor directly on Posidonia oceanica seagrass beds in French Mediterranean waters, not cruising or swimming in the same areas
- Where it applies: the French Riviera and Corsica, with the strictest rules inside marine parks such as Port-Cros/Porquerolles, the Calanques National Park, and Scandola in Corsica
- Who it affects: the most commonly cited size threshold for the core rule is 24 metres and above, though smaller yachts are also restricted inside specific mapped zones
- What happens if it’s ignored: real, enforced fines, reported as high as €150,000, plus possible navigation bans from French waters
- How we handle it: our captains use organized, eco-friendly mooring buoy fields (called ZMEL) and current official charts instead of free-anchoring in a restricted spot
What Is Posidonia Seagrass, and Why Does France Protect It?
Posidonia oceanica is a native Mediterranean seagrass, not an algae, and it grows in dense underwater meadows along much of the French Riviera and Corsican coastline. It has been a protected species in France since 1988. The meadows matter because they support marine life, help keep the water clear, and grow extremely slowly. A single anchor drop and retrieval can tear out rhizomes that take far longer than a human lifetime to recover.
That is the reason behind the anchoring restrictions covered below, and it is worth knowing, but it is not the part of this that actually affects your week on board. The next section is.
What the Anchoring Rules Actually Restrict
The rule governs where the anchor and chain touch the seabed, not where the yacht can go. A boat can cruise, swim, and moor near a protected meadow; it just cannot drop anchor directly on top of it.
France introduced the core framework for this in a 2019 maritime decree (No. 123/2019), which the Préfecture maritime de la Méditerranée then rolled out through a series of department-by-department decrees starting in Alpes-Maritimes in October 2020 and continuing across the rest of the Mediterranean coast. The most commonly cited size threshold for this rule is yachts of 24 metres and above, though the exact figure has varied slightly by department and by year as each decree was issued and updated.
Smaller yachts are not automatically exempt. Inside specific mapped protection zones, primarily marine parks and reserves, smaller vessels are restricted too. A separate, later decree from 2024 added its own rule tier for the largest vessels, generally defined around 45 metres or 300 gross tons — a distinct layer aimed at the superyacht end of the market, on top of, not instead of, the core Posidonia rule.
Because the exact zones and thresholds are set and updated by prefectoral decree year to year, we do not treat any single number as a fixed rule for every yacht. Our captains check the current chart for the relevant department before each charter rather than relying on a rule of thumb.
Where This Comes Up Most on a Riviera or Corsica Charter
The strictest, best-known protected areas along a typical South of France route are the Port-Cros and Porquerolles national park waters off Hyères, the Calanques National Park near Marseille, and the Scandola nature reserve in Corsica. These are established marine protected areas with their own anchoring rules layered on top of the general Posidonia decree.
If your route follows the classic 7-day Riviera itinerary from Antibes to Monaco, it passes close to several of these zones, including the waters off Porquerolles. A route that continues on to Corsica or Sardinia adds Scandola into the mix. None of this rules out those stops. It just means your captain plans the exact anchoring spot inside each bay with the current chart in hand, rather than picking a spot on sight.
We are not going to list exact anchoring coordinates here, because the mapped zones are reviewed and can shift from one season to the next. If you want the specific detail for your route before you book, we can pull the current chart for your captain to review with you.
How We Handle This on a Crewed Charter
Clients sometimes ask whether this rule means they will not get the exact swim spot or anchorage they had in mind. That is a completely normal question, and the honest answer is: almost never, once a route is planned properly.
The fix is not “anchor somewhere less nice.” It is anchoring in the same bay using a spot outside the seagrass meadow, or using one of the organized mooring buoy fields, called ZMEL, that France has installed specifically so boats have a straightforward, legal place to tie up without touching protected seabed. These buoys are placed outside seagrass beds and are the standard alternative captains use in restricted areas.
We check the current anchoring charts before every Riviera or Corsica charter, so this is already factored into the route before you arrive. It is a captain’s planning task, not something you need to manage, and it almost never changes which bay, beach club, or swim spot ends up on your itinerary. It changes where inside that bay the anchor actually goes down.
“Our captains treat this as a morning logistics problem, not just a legal one. Around Saint-Tropez and Pampelonne in peak season, the legal ZMEL mooring buoys outside the seagrass beds fill up fast, often by mid-morning. So the route gets built with an early move or a backup bay already picked, rather than arriving at 1pm and discovering the legal spots are taken.”
Our South of France Team, DMA Yachting
What Happens If the Rules Are Ignored
This is not a theoretical rule. In October 2023, the Maritime Court of Marseille convicted the captain of a 26-metre yacht after three separate anchoring violations, twice in Cannes in 2021 and once in Saint-Tropez in 2022. The captain was fined €20,000 and banned from navigating in French Mediterranean waters for a year. Reported penalties for serious Posidonia destruction can go considerably higher, with fines cited as high as €150,000 under French environmental law, plus the possibility of a longer navigation ban.
That is exactly why every reputable operator checks the chart first rather than treating it as a risk worth taking. It is also why this is worth knowing as a client: it is a real, enforced rule, and it is one more reason to charter with a captain and brokerage who already build it into route planning instead of leaving it to chance.
Our Recommendation
The anchoring restrictions on Posidonia seagrass should not change which destinations, beach clubs, or swim spots you ask for on a Riviera or Corsica charter. They change how the captain executes the details once you are there, and that part is already our job.
Zones and thresholds are reviewed and updated most years, so it is worth confirming the current rules with your broker or captain before you lock in an anchoring wishlist, rather than relying on anything you read online, including this page.
Send us your wishlist, the anchorages you have heard about, the beach clubs you want to reach by yacht, and any must-see stops, and we will build a route around them with the current rules already factored in.
Contact our South of France charter team or start with our French Riviera yacht charter page.
FAQ
Does the Posidonia anchoring rule apply to my whole charter, or just certain spots?
Only to certain spots. The rule restricts anchoring directly on Posidonia seagrass beds in specific mapped zones, mainly along the Riviera coast, in marine parks such as Port-Cros/Porquerolles and the Calanques, and around Scandola in Corsica. It does not restrict cruising, swimming, or mooring in general.
Will this change where my yacht can go on a French Riviera charter?
Almost never in practice. It can change exactly where inside a bay the anchor drops, but a well-planned route reaches the same destinations, beaches, and beach clubs using an approved anchoring spot or an organized mooring buoy instead of an unrestricted spot.
What size yacht does the anchoring restriction apply to?
The most commonly cited threshold for the core rule is 24 metres and above, though smaller yachts are also restricted inside specific protected zones, and the exact figures vary by department and are updated periodically. Your captain checks the current rule for your route rather than relying on one fixed number.
What happens if a captain anchors somewhere restricted?
Penalties are real. A 2023 case saw a yacht captain fined €20,000 and banned from French Mediterranean waters for a year after repeated violations, and reported fines for serious cases can run considerably higher. This is actively enforced, which is why route planning around it matters.
Do I need to do anything about this myself?
No. Checking anchoring charts and choosing compliant spots is a captain and brokerage task. Your role is to tell us the places you want to see; ours is to get you there within the current rules.
