It’s no secret that come summer, the alluring coastline of southern Portugal — better known as the Algarve — practically sags under the crush of holidaymakers who throng its vacation villages, resort hotels, marinas, 18-hole links, beachwear boutiques, souvenir emporiums, seaside cafes and seasonal discos.Blame the Algarve’s good looks. Stretching from the Spanish border nearly 100 miles along the Atlantic coast to the very southwestern tip of the Continent, the seaside is blessed with windswept dunes, powdery sands, ocher cliffs and natural grottoes. The seafood can be sublime and the prices extremely modest, especially compared with summer havens like Italy’s Amalfi Coast or the French Riviera.With such an irresistible cocktail of scenery and values, it’s no wonder that some 2 million foreigners — primarily from Great Britain — flood these expanses. Some two-thirds of the flights to Faro, the gateway to the region, arrive from London, Leeds, Liverpool, Dublin and their neighbors, transforming popular towns like Albufeira into variants of Brighton with more powerful UV rays. Menus feature fish and chips. English Premier League football matches flicker from screens in bars. No euros in your pocket? Just pay in pounds sterling.The human density of high summer was conjured most vividly as I gazed out from the terrace of the Hotel Bela Vista, a Moorish-style mansion surrounded by charmless high-rise hotels on a cliff overlooking the enormous Praia da Rocha beach.“In July and August, you can’t find a single space to put your towel,” said Gonçalo Narciso, the hotel’s operations manager. He shook his head. “You can’t imagine.”Amid the sunscreen-smeared hullabaloo, the question arises: Is there an alternative Algarve? A less-trod Algarve? An Algarve where a bit of serenity and the flavor of the past have been preserved? In quest of such a place, I set off in late May to travel beyond the universe of half-board arrangements and karaoke nights. Carried by the region’s efficient EVA bus network, I traveled along rocky coasts and sun-baked hills, pleasantly surprised to find fishing villages and citadel towns where a more traditional Algarve still exists, and, in the case of one tiny hamlet, Pedralva, is being reborn. From storybook medieval castles to unmarked surfer beaches to mom-and-pop seafood joints, this unspoiled Algarve, it turned out, is available to anyone with bus fare and an urge to go against the flow.TaviraFollowing a three-hour train journey from Lisbon to Faro, and a one-hour bus ride through uninspiring back roads, I landed in Tavira, a coastal town near the Spanish border with vestiges of ancient Phoenician and Roman settlements lurking under its streets. Whitewashed buildings with wrought-iron balconies filled narrow lanes, along with numerous Renaissance and Baroque churches — testaments to the town’s wealth generated long ago from the fishing and salt trades. Even today, the shallow, shimmering tidal pools of the salt pans do their quiet work just outside the town.On a stone bridge spanning the Gilo River, which splits the town in two and flows into the Atlantic, a three-piece band of guitar, accordion and tambourine played spirited folk songs. More music spilled out from the tile-lined interior of the Renaissance-era Church of Misericordia, where a bearded hipster schoolteacher was strumming a guitar while leading boys and girls, dressed in pink smocks, in a soaring hymn. Above, atop a hillside, the ruins of a medieval castle and the clock tower of the 18th-century Santa Maria do Castelo church lorded over a sea of orange-tile roofs.The salt breeze suffused the town with an agreeable torpor as I strolled toward Praa da Repblica, the town hall square, for a rendezvous with a resident. In the middle of the riverbed, men toting plastic buckets yanked mussels from small, rocky islands revealed by the low tide. A few German and French voices drifted from sidewalk cafes, though hardly enough to drown out the locals’ mellifluous Portuguese greetings of “Bom dia!” and “Tudo bem?”“The essence of eastern Algarve is its authenticity,” said Tim Robinson, a stocky, blond Englishman, who welcomed me on the terrace of a cafe called Veneza. “This is really where the old Portuguese way of life is being retained. Later, exploring Tavira on foot, I found resurrected historic edifices scattered all over. The town’s former covered market — a lovely wrought-iron structure from the 1880s — bustled with boutiques and restaurants. Farther afield, some new white walls and oddly angled metal surfaces had elevated a former jail into a modern town library. Just around the corner, a renovation plan by the Portuguese architect Eduardo Souto de Moura, who won the Pritzker Prize two years ago, was transforming the Renaissance-era Convento das Bernardas into luxury apartments.Entering the majestic 16th-century Palacio da Galeria, I discovered the municipal museum. This year’s big show, “Dieta Mediterranica,” runs into 2014 and is dedicated to the foods of the Algarve. (Though the Algarve is not on the Mediterranean, the show asserts that the region “is influenced by the Mediterranean climate.”Amid displays of the Algarve’s cornucopia — baskets of dried carob, sacks of sea salt, bottles of olive oil, tins of tuna, piles of figs — information stenciled on the walls imparted intriguing facts (“Portugal is the third-largest consumer of fish in the world, immediately after Japan and Iceland”). Suddenly, I was ravenous. Fortunately, my visit coincided with Tavira’s annual two-week Festival de Gastronomia do Mar, a homage to seafood. Many restaurants had assembled special menus to showcase local tuna, mackerel, octopus, mussels, clams and other briny bounty.Praia da Rocha and SilvesI encountered mainstream Algarve in Praia da Rocha, a sprawling beach resort in western Algarve — the first spot in the region to be frequented by tourists. That was more than a century ago. Today the cradle of Algarve holidaymaking represents all of the triumphs and tragedies (mainly aesthetic) of the region’s rise from provincial backwater to international getaway.Triumph: the sublime beauty of golden sands backed by jagged red cliffs. Tragedy: the stampede of summer vacationers who pack its beach clubs and bars. Triumph: a 17th-century fortress and century-old villas that dot the cliff-top streets. Tragedy: generic condo developments and uninspired hotels. Triumph: fresh seafood, everywhere. Tragedy: pints of Guinness, everywhere.But even here one can find remnants of an unspoiled Algarve. They lie beyond the gates of the Hotel Bela Vista, the extravagantly restored century-old Moorish mansion that claims to be the Algarve’s first hotel. Within I marveled at black-and-white photographs of Praia da Rocha in the early 20th century. The building’s exotic silhouette stands out starkly against a nearly empty beachfront. Stepping out of that hushed prelapsarian era into the vividly colored clamor of modern Praia da Rocha’s souvenir stands, cheap Chinese restaurants and Irish bars was like experiencing expulsion from Eden, touristically speaking.A local bus whisked me into the backcountry, past lemon trees and orange groves. After 20 minutes a hilltop fortress came into view, its red-stone battlements hovering over a village that spilled down the hillside toward a river.Winding my way up the cobbled streets of the town, Silves (pronounced SIL-vish), I found Maria Gonalves, the chief municipal archaeologist, seated at a table in the castle’s lushly planted grounds. A few couples roamed the ramparts, peering through the crenelations as Gonalves filled me in on the history of the town and the structure, the largest and best-preserved castle in the Algarve.“They were Arabs from Yemen during the first half of the 11th century,” she said of the original settlers and rulers, who arrived at the time of the Moorish occupation of Andalusia, in neighboring Spain. Silves became the capital of Al-Gharb Al-Andalus, as the Arabs called the region: the west of Andalusia (“al-Gharb,” meaning “the West,” later became Algarve). The city was known as a cultural hub.“There were lots of important poets from that period,” she said, most notably Al-Mutamid, who also happened to be the governor of Silves (and later the king of Seville). “He describes Silves as a town of indulgence. The palace. The ‘white gazelles’ — the women. The banks of the river.”Dynasties from North Africa later seized the city, and Silves was eventually conquered by Christian crusaders. But the Arab influence remains omnipresent.PedralvaThe final push to the western edge of the Algarve, Europe’s far southwestern corner, landed me briefly in the port town of Lagos. Along its palm-lined marina, hawkers approached with fliers for snorkeling adventures, whale-watching, sport fishing, kite-surfing and sightseeing cruises.But I was headed to farther shores. Another bus continued westward over waves of brown hills dotted with ruined stone houses and tiny lime-washed villages. In a village called Vila do Bispo, a car from the nearby hamlet of Pedralva picked me up and deposited me amid its stone-paved streets and restored white stone houses.The village’s existence is an Algarve miracle. Several years ago, Pedralva was on the brink of ruin. The population had dwindled to nine residents, and many of the 19th-century houses were abandoned wrecks.“It was a complete ghost town,” said Antonio Ferreira, a former Lisbon advertising strategist who effectively saved Pedralva by transforming it into one of the most original new getaways in the Algarve.In 2010 they opened Aldeia da Pedralva, an eco-tourism village replete with cobbled lanes, whitewashed houses, a grocery store and a traditional Algarve restaurant. “The idea here is to cut off from the life that you have in big cities, or even small cities: cars, traffic, lots of information, lots of advertising, mobile phones,” he said in the village’s reception area, where we sat drinking coffee. Outside the window, in a quiet valley of pine and cork trees, no nightclub pounded, no driving range beckoned. Occasionally a rooster crowed.“We are the other Algarve,” Ferreira said. “This is the unspoiled Algarve.”Keen to see the coast — the true end of the world, or at least the Continent — I hitched a ride with a villager to Praia do Amado, a few miles away at the end of an unmarked road.That night, after lamb chops and local red wine in one of the two Pedralva restaurants, I retired to my cottage with its timber ceiling and wood furnishings in funky colors. No television, cellphone signal or Internet link distracted me from the silence and the stars. The only sounds were those of owls and crickets in the surrounding valley: the voices of the unspoiled Algarve.