After a quick tour of Giresun’s fish market, a small L-shaped collection of open stalls a block from the harbor, I headed to Emre Balikcilik (51 Fatih Caddesi; 90-454-212-7200), a fish shop and cafe where the day’s catch is cooked in an open kitchen. Turken Tunan, who owns the spot with her husband, is a specialist in tava, a regional technique for preparing fish. She dipped my anchovies in corn flour, arranged them in a spiral formation in the pan and sautéed them over high heat, flipping them like an omelet midway. They were fantastically crispy, fragrant thanks to the corn flour and not at all oily. For her buglama (“Not hamsi for this, but bluefish,” she noted) Ms. Tunan laid paper-thin slices of garlic and peeled and sliced tomatoes over the fish, sprinkled them with crushed dried red chile and added a shocking amount of butter. After 15 minutes on top of the stove, the tomatoes had melted onto the fish, which now swam in a luxuriously buttery tomato sauce.

From Giresun I drove west, diverting right after Ordu from the main highway to a sinuous stretch of two-lane blacktop marked by small harbors clogged with fishing trawlers. On a grassy peninsula I came upon a 19th-century Greek Orthodox church built on the site of a temple dedicated to Jason of the Argonauts. A bit farther on, I stopped for worship of a different kind at Vonali Celal (Caka Tunel Mevki; 90-452-587-2137), an endearingly quirky restaurant perched over the sea, appended to a half-century-old pickle shop.

Suleyman, the younger brother of the restaurant’s eponymous founder, led me past sagging shelves displaying hundreds of brining jars, housing everything from yellow cherries and sour plums to whole cloves of garlic and stuffed eggplants. At a table warmed by the wood stove I ate a top-notch hamsi tava, which arrived garnished with singed slices of onion and long green peppers. Also noteworthy: Black Sea dishes like small griddled corn breads, eaten with sautéed pickled Romano beans; and a frittata made with tiny local onions called sakarca. Next up was Unye, where I passed the hours between anchovy sampling by admiring the town’s impressive collection of Ottoman mansions, shopping at its old-style copper shops and strolling along its long stretch of seaside promenade.

The morning after my impromptu feast at Sehrazade the weather turned springlike — and the hamsi disappeared. I made do with a solid buglama (I was learning that there are as many versions of this dish as there are Black Sea cooks) featuring thick slices of bonito at Iskele Restoran (67 Hukumet Caddesi; 90-452-323-4469), a sleek businessmen’s hangout overlooking the beach, then pushed west.

The 160-mile drive to Sinop was the most punishing of my trip, an unlovely four-hour slog through roadwork and a mess of overpass construction in downtown Samsun. But the effort was rewarded in Sinop, whose lovely old town bends around a small working harbor lined with teahouses made for idling, all bookended by the crenelated ruins of a citadel possibly dating to Roman times.