Load the sailboat with bottles of white wine, olive oil, fishing rods, and yeasty, dark-crusted bread. Work your way carefully out of the narrow channels of the Cabras port on the western shore of Sardinia. Set sail for the open seas.
Navigate carefully around the archipelago of small boats fishing for sea bass, bream, squid. Steer clear of the lines of mussel nets swooping in long black arcs off the coastline. When you spot the crumbling stone tower, turn the boat north and nuzzle it gently into the electric blue-green waters along ancient Tharros. Drop anchor.
Strip down to your bathing suit. Load into the transport boat and head for shore. After a swim, make for the highest point on the peninsula, the one with the view of land and sea and history that will make your knees buckle. Stay focused. You're not here to admire the sun-baked ruins of one of Sardinia's oldest civilizations, a five-thousand-year-old settlement that wears the footprints of its inhabitants- Phoenicians, Greeks, Romans- like the layers of a cake. You're here to pick herbs growing wildly among the ancient tombs and temples, under shards of broken vases once holding humans' earliest attempts at inebriation. Taste this! Like peppermint, but spicy. And this! A version of wild lemon thyme, perfect with seafood. Pluck a handful of finocchio marino,sea fennel, a bright burst of anise with an undertow of salt.
Withfinocchioin fist, reboard the transport vessel and navigate toward the closest buoy. Grab the bright orange plastic, roll it over, and scrape off the thicket of mussels growing beneath. Repeat with the other buoys until you have enough mussels to fill a pot.
In the belly of the boat, bring the dish together: Scrub the mussels. Bring a pot of seawater to a raucous boil and drop in the spaghetti- cento grammi a testa. While the pasta cooks, blanch a few handfuls of the wild fennel to take away some of the sting. Remove the mussels from their shells and combine with sliced garlic, a glass of seawater, and a deluge of peppery local olive oil in a pan. Take the pasta constantly, checking for doneness. (Don't you dare overcook it!) When only the faintest resistance remains in the middle, drain and add to the pan of mussels. Move the pasta fast and frequently with a pair of tongs, emulsifying the water and mussel juice with the oil. Keep stirring and drizzling in oil until a glistening sheen forms on the surface of the pasta. This is called la mantecatura, the key to all great seafood pastas, so take the time to do it right.