Mediterranean Anchoring: Technique, Ground Tackle and the Posidonia Rules

Anchoring in the Mediterranean is a different discipline from anchoring in tidal Northern Europe. Depths in an average bay are 8-18 metres rather than 3-6, the bottom is often a patchwork of sand and protected seagrass, and the wind that matters usually arrives at three in the morning.

Ground tackle first

Most production boats leave the factory under-anchored. For a 12m cruiser in the Med, the working standard is a 20-25kg modern scoop anchor — Rocna, Spade, Mantus or Ultra — on at least 60 metres of 10mm chain, with a 15m nylon snubber. Old-generation CQR and Delta anchors will hold once set but are markedly worse at setting first time in weed and thin sand, and first-time setting is the whole game when you arrive in a crowded bay at 18:00.

Mark the chain every 10 metres in a repeating colour sequence and read the marks, not the windlass counter.

Scope in deep water

The familiar 5:1 rule becomes unaffordable in 15 metres. In practice, all-chain rodes in settled conditions work at 4:1 measured from the bow roller — so 15m of depth plus 1.5m of freeboard is 66 metres of chain. In a forecast blow, go to 5:1 or more, or move to a bay with shallower sand. If you cannot lay enough chain to swing safely without hitting a neighbour, the bay is full; go somewhere else rather than laying short.

The setting routine

Motor slowly over the spot and check the sounder and the water colour: pale patches are sand, dark patches are weed or rock. Drop with the boat stopped, not moving astern, then reverse gently while the chain runs so it lays out straight. When all the chain is out, snub it and apply 1,500-1,800rpm astern for thirty seconds while watching a transit ashore. If the transit moves, you are dragging — recover and repeat. Put a hand on the chain: a dragging anchor sends a distinct rumble up the rode.

Finally, swim on it. Water clarity is the Mediterranean''s great gift: two minutes with a mask tells you more than any instrument.

Posidonia and the law

Posidonia oceanica is a protected seagrass across Spain, France, Italy and Croatia, and anchoring in it is now enforced. In the Balearics, fines run into the thousands of euros and drone and patrol enforcement is routine in Formentera and around the Cabrera archipelago; parts of the French Riviera prohibit anchoring outright for larger vessels. Use a posidonia-mapping app, anchor only in sand, and lay chain so it does not sweep across a seagrass meadow as you swing.

Night watch discipline

Set an anchor alarm with a radius based on your actual scope plus boat length, not a default 30 metres. Note the bearing and distance to the nearest boat before dark. If a bay is exposed to the direction the wind is forecast to back into overnight, accept the marina fee instead — the Med''s katabatic winds arrive fast and the coastline is steep-to, which leaves very little sea room when you wake up to 35 knots.

Med-mooring on the town quay

Where anchoring is not an option, the stern-to routine is the same everywhere: prepare two long stern lines and fenders, drop the anchor four to five boat lengths off the quay square to your berth, reverse straight with the chain paying out under light tension, and take the windward stern line first. Do not cross your chain over your neighbour''s — recovering it at 07:00 in front of an audience is the sort of thing you only do once.