A bluefin tuna is lifted during the opening of the season for tuna fishing in the port of Barbate in the Cádiz province of southern Spain. (Emilio Morenatti/AP)

Ignoring the warnings of the ancient Phoenicians, I sailed past the legendary Pillars of Hercules, the mountains that flank the Strait of Gibraltar, and didn’t fall off the edge of the world. Instead, well-anchored on the ferry that links Spain to Morocco in less than an hour, and savoring the impossibly fluffy croissant I’d bought from the floating cafeteria, I pondered the rich history that lay in the choppy waters between Europe and Africa.

Details on Andalusia

When the Arabs crossed the Strait of Gibraltar in 711, they stretched their Muslim empire into the Iberian Peninsula, named it Al-Andalus, and settled there for seven centuries. On an earlier trip to Southern Spain, I had visited Seville, Granada and Cordoba and been awed by the amalgam of cultures I found there, reflected in everything from the architecture to the local cuisine. Indeed, the Arab influence felt so palpable that this time, I chose to start my seven-day journey through a less well-known corner of southwestern Andalusia in . . . Tangier, Morocco.

“Welcome to your country,” announced the monumental sign outside the ferry terminal, somewhat ambiguously, in Arabic and French.

“Buenos Dias! Bonjour!” said Abdelaziz Benali Deghali, an aristocratic-looking guide clad in traditional djellaba and fez whom I’d booked to help me navigate the city.

Because of its strategic position, Tangier has long been a key trading port. But from 1923 to 1956 (except when Spanish dictator Francisco Franco occupied it from 1940 to 1945), while Morocco became a French protectorate, Tangier held a unique international zone status, attracting artists and expats including Paul Bowles and Tennessee Williams.

More than its multilingual nature, what struck me most were the multi­colored accents that caught my eye everywhere I walked in the medina, or old town: against the perfect white of the flat roofs that dot the hills, shiny green tiles (the official color of Islam) shone on the roofs of the mosques; at the market, garnet prawns the size of small chickens lay curled up near rainbow-colored beets; along ancient craggy facades, bursts of fuchsia bougainvillea hung in heavy clusters.

“What do you have that no one else has?” I asked Deghali’s favorite spice merchant.

“But we all sell the same things,” he laughed. “The difference is the people.”

And the people of Tangier are bustling more than ever. In the past five years, the king of Morocco has poured resources into modernizing the city. Next to the minarets, cranes rose toward the sky, but I gasped at the layers of beauty and history peeling off a round wooden door surrounded by lacy strings of stone and yellow and blue mosaic tiles. It wasn’t the future of Tangier that I was chasing.

Attuned to tuna

The next day, back in Tarifa, Spain, Ignacio Soto was waiting for me. A silver-haired sailor with a nonchalant elegance, Soto happens to count Christopher Columbus among his ancestors. He runs Nature Tarifa, a company that offers all manner of nautical excursions, but is most passionate about the rich biodiversity of the area. “More than 25 million birds migrate every year from one continent to the other,” he said, and then with a captain’s authority announced proudly, “We are now the only group allowed to take travelers to watch the almadraba.” He was referring to the historic tuna net-fishing technique that capitalizes on the spring migration of the fish into the Mediterranean. These fishing rights were granted to noble families centuries ago, have been passed along through generations and are still tightly held.

“Phoenicians, the kings of trade, settled in this area first, because of the access to Africa, the tunas and the salt marshes,” he explained as we drove nine miles to the stunning Roman ruins of Baelo Claudia and its well-preserved fish-salting factory, set just a few feet from the water. In the adjoining museum, Soto pointed to the tunas engraved on ancient coins and amphorae. All this talk of tuna made me hungry, so he took me to La Taberna de El Campero in the nearby town of Zahara de los Atunes. There, among more than 20 tuna preparations, none from a can, we feasted on mojama, an intense dried salted bluefin, and atún de ijar, the rich belly cured in oil.

I climbed back into Soto’s Jeep for the short half-hour ride to the hill town of Vejer de la Frontera, one of the latest additions to an unofficial list of the “most beautiful villages of Spain.” Even though progress in the form of a sushi stall has landed in the covered market, “life in Vejer is tranquil,” said Maria Angeles, a fifth-generation grocery owner. No cars, white-washed square houses concealing flowery patios, a Moorish legacy and killer views of distant Morocco have attracted a lively contingent of expats. In Vejer, the candy seller is the mayor’s father, the butcher takes such good care of his customers that he provides benches for waiting, and the minaret of the old mosque is now part of the church. And then there’s Annie Manson, a petite rosy-cheeked Scottish emigré who came on vacation 10 years ago and never left.

“It’s good for you,” she said to me the next day, prodding me to break off the head and tail of slippery, slimy anchovies. I’d signed up for one of the hands-on Spanish cooking classes she cheerfully dispenses from her sleek professional kitchen. After a few hours of prep work, many laughs and slightly more than our quota of local sherry, we downed a melon and mint gazpacho and a chickpea stew with chorizo and squid.

Sweet on sherry

But to find Neptune, it’s worth driving 35 miles for a splurge at Restaurante Aponiente in El Puerto de Santa María, a lively seaport town, where Ángel León, the son of a local fisherman, has built a Michelin-starred high temple to the underwater world.

After a delicious 15-course tasting menu including plankton risotto and razor clam crudo, Annie and I strolled alongside the 18th-century mansions until we came upon a man rolling a wooden barrel into the street. We followed him into the Gutiérrez Colosía sherry bodega. Sherry, a fortified wine, derives its name from Sherish, the Arab moniker of the city of Jerez de la Frontera.

“In the world of sherry,” said co-owner Carmen Pou, “the grapes don’t matter; the bodega does.”

I was expecting a cellar; I found a cathedral of sherry. Literally. Under 40-foot vaults supported by stone arches, rows and rows of stacked barrels soaked in the narrow rays of light that descended from the ceiling. I joined a small group of connoisseurs and tasted crisp fino and aromatic amontillado; but based on the sophisticated comments of others in the group, it was obvious that I needed a real education. So the next day, I drove the easy half hour to Jerez.

Along the modern highway, marshes dotted with pink flamingoes alternated with chalky fields, betraying the powdery limestone essential to the white grapes that make up sherry. Here and there, storks perched on their bushy nests, surveying the countryside.

Jerez, which was named “European Wine City 2014” by Recevin, an association of European wine towns, boasts 26 sherry bodegas, most of them open to the public. Curious about the English love affair with sherry, I arranged to meet José Luís Jiménez García, a sherry scholar.

In the historic center, where Moorish, Renaissance and baroque styles fuse at every corner, we sat on a leafy plaza, surrounded by white mansions flaunting glass-enclosed balconies lined with ochre-tinted paint.

“After the Hundred Years’ War between France and England,” he said, as he drizzled olive oil and tomato salmorejo onto his breakfast toast, “the British asked the French to barter wine for wool, but they were rebuked, so that they bypassed France and focused on Spain.” He explained that the first train line in Andalusia was built through the vineyards so the grapes could be brought directly onto English ships.

Again, as in Tangier, I felt the ancient ways coursing just beneath the present-day landscape. That night, I followed José from tapas bars to tabancos, where sherry is drawn directly from the barrels.

Beyond the history books

Still a bit wobbly the next day, I traveled by train to Cádiz, one of Europe’s oldest cities. It wasn’t easy to find an open cafe on a Sunday, but when I did, across from what looked like a Roman temple but turned out to be a shuttered covered market, I ordered what everyone seemed to be enjoying: churros. An older couple laughed as I burned my fingers while dunking the fried dough in my thick hot chocolate, but later on, when I asked for the check, I learned that they had settled it for me.

Touched, I strolled around, admiring sea gulls plucking at the old stone high up near the golden dome of the baroque cathedral. At the beach, the family next to me paid for my drink, and that night at La Candela, a new tapas bar, the chef offered me a fino.

In 1717, Cádiz became the official port of entry for all American goods; wealth ensued. Was this why, centuries later, upon hearing that I was from the New World, Gaditanos, as the city’s residents are known, rushed to pay for my drinks?

On my last evening in the city, I stood in the Cádiz Museum, mesmerized by two huge Phoenician sarcophagi; the 1887 discovery of one had spurred the museum’s creation. Until recently, the Phoenicians had been just a chapter in my sixth-grade history book, I mused. But on this trip, as I’d roamed along their ancient trade routes, defied their warnings and not fallen off the edge of the earth, I had, somehow, established a mysterious kinship.

Bigar is a New York-based food and travel writer.

Editor’s note: A previous version of this article omitted a listing for Annie B’s Spanish Kitchen.