The sun-drenched resort of Puerto Vallarta (pop. 350,000) and its surrounding region owe their prosperity to their most fortunate location, where gentle Pacific breezes meet the parade of majestic volcanic peaks marching west from central Mexico. Breeze-borne moisture, trickling down mineral-rich volcanic slopes, has nurtured civilizations for millennia in the highland valleys around Tepic and Guadalajara, the state capitals of Nayarit and Jalisco. Running from Lake Chapala, just south of Guadalajara, the waters plunge into the mile-deep canyon of Mexico’s longest river, the Río Grande de Santiago (known as the Río Lerma upstream of the lake). They finally return to the ocean, nourishing the teeming aquatic life of the river’s estuary just north of San Blas, Nayarit, two hours’ drive north of Puerto Vallarta.

Within sight of Puerto Vallarta rise the jagged mountain ranges of the Sierra Vallejo and the Sierra Cuale. The runoff from these peaks becomes the Río Ameca, which sustains a lush patchwork of fruit, corn, and sugarcane that decorates the broad valley bottom. The Ameca meets the ocean just north of Puerto Vallarta town limits. There, myriad sea creatures seek the river’s nourishment at the Puerto Vallarta shoreline, the innermost recess of the Bay of Banderas, Mexico’s broadest and deepest bay.

On the map of the Puerto Vallarta region, the Bay of Banderas appears gouged from the coast by some vengeful Aztec god (perhaps in retribution for the Spanish conquest) with a single 20-mile-wide swipe of his giant hand, just sparing the city of Puerto Vallarta.

Time, however, appears to have healed that great imaginary cataclysm. The rugged Sierra Vallejo to the north and Sierra Cuale to the south have acquired green coats of jungly forest on their slopes, and sand has accumulated on the great arc of the Bay of Banderas. There, a diadem of palmy fishing villages—Punta Mita, Cruz de Huanacaxtle, Bucerías, Mismaloya, Boca de Tomatlán, and Yelapa—decorate the bay to the north and south of town. In the mountains that rise literally from Puerto Vallarta’s city streets, the idyllic colonial-era villages of San Sebastián, Mascota, and Talpa nestle in verdant valleys only 20 minutes away by light plane.

Farther afield, smaller bays dotted with pearly strands, sleepy villages, and small resorts adorn the coastline north and south of the Bay of Banderas. To the south, beyond the pine- and oak-studded Sierra Lagunillas summit, stretch the blue reaches of the bays of Chamela, Tenacatita, and, finally, Navidad, at the Jalisco-Colima state border. There, the downscale little resort of Barra de Navidad drowses beside its wildlife-rich lagoon.

To the north of the Bay of Banderas stretches the vine-strewn Nayarit Coast, where the broad inlets of Jaltemba and Matanchén curve past the sleepy winter havens of Sayulita, Rincón de Guayabitos, and San Blas. From there, a mangrove marshland extends past the historic Mexcaltitán island-village to the jungly Río Cañas at the Nayarit-Sinaloa border.