Some of Puerto Rico's most beautiful and isolated beaches lie on the island's southwestern coast, on the Caribbean Sea, far from major highways. Stretching between Ponce in the east and Cabo Rojo on Puerto Rico's extreme southwestern tip, these beaches flank some of the least densely populated parts of the island. And because the boundaries between them are relatively fluid, only a local resident (or perhaps a professional geographer) could say for sure where one ends and the other begins.
If you consider yourself an aficionado of isolated beaches, it's worth renting a car and striking out for these remote locales. Drive westward from Ponce along Highway 2, branching south along Route 116 to Guánica, the self-anointed gateway and capital of this string of "secret beaches."
By far the most accessible and appealing beach is Caña Gorda. Set about a quarter-mile (.4km) south of Guánica, at the edge of a legally protected marsh that's known for its rich bird life and thick reeds, Caña Gorda is a sprawling expanse of pale beige sand that's dotted with ramshackle-looking bohios (huts) crafted from tree branches and palm fronds. Despite its rusticity, it's a site that's been improved and developed by the local authorities. The centerpiece here is a well-recommended hotel, the Copamarina (tel. 800/981-4676 or 787/821-0505). You can check in for a night or two of sun-flooded R&R. Even if you're not staying at the hotel, consider dropping in for a cuba libre, a margarita, or a meal.
In the very southwest sector of Puerto Rico are some relatively hidden and very secluded beaches, although getting to them is a bit difficult along some potholed roads. From Boquerón head east on Route 101, cutting south at the junction with Route 301 which will carry you to the one of the most westerly beaches in Puerto Rico, Playa Sucia. The beach opens onto Bahia Sucia, whose name rather unappetizingly translates as "Dirty Bay." Actually it isn't dirty; it's a lovely spot.
From Bahia Sucia, you can head east to discover other secret beaches, which are reached along various signposted roads: 324, 304, and 323. The finest beaches, moving toward Ponce, are Rosado Beach, Playa Santa, and Playa Tamarindo.
All these beaches might be hard to reach, but persevere and you'll be met with warm water and long, uncrowded stretches of sand, where towering king palms and salt-tolerant sea grapes provide an idyllic tropical backdrop for sun and surf. Keep in mind that with the exception of Caña Gorda, the beaches mentioned here have virtually no services and public utilities. Pack what you'll need for the day -- food, water, sunscreen, and so forth.