Where to stay
Villas del Mar Hau
Isabela, northwest coast
Small, 42-unit complex of bungalows and two-story villas with four hotel rooms each, on a great swimming beach. Pool, horse riding nearby. Surfing. Cottages have fully equipped kitchens. High-season prices range from $100 per night for basic room to $250 per night for three-bedroom unit.
Bahía Salinas Beach Resort
Boqueron, Cabo Rojo
Renovated 22-room resort hotel on a mangrove bay (not swimmable) with two pools. Isolated, quiet. Beaches nearby. Slow restaurant service. Basic room $110-$250 per night. Weekend packages available.
Friendly 74-room family-oriented 1950s-style hotel in village on Parguera Bay. No swimming beach at hotel but launches for hire to nearby mangroves and coral reef. Good restaurant, walkable to several simple eateries. On Bioluminescent Bay. Seaview room for two, $100 per night. With breakfast and dinner for two, $150 per night. Weekend packages available.
What to do
Near Isabela. Third-largest cave complex in the world. Trails go down 200 feet. Open Wednesday-Sunday, 8 a.m.-4 p.m. 787-898-3100.
South of Arecibo. The world's largest single-dish radio telescope, featured in the movie "Contact." Excellent astronomy museum. With planning, easy to do Camuy Caves and observatory in a full-day trip. Open Wednesday-Friday, noon-4 p.m., and weekends 9 a.m.-4 .
Beaches Near Bahía Salinas: Boqueron Beach, big, public beach; Combate Beach; Cabo Rojo lighthouse, in a small nature reserve at the tip of the island, with pretty curving beach.
Bioluminescent Bay Near Parguera. Take evening launch from pier to visit site of eerie light churned up in sea from rich plankton.
Where to eat
Puerto Rico offers an endless variety of simple family restaurants along the beaches. For a splurge, eat at the Copamarina Beach Resort, by far the most luxurious resort on the southwestern coast, at Guánica in the UNESCO dry forest reserve. For lunch near Arecibo, El Observatorio on Route 625, a simple and pleasant restaurant. Upmarket, near Isabela, the Villa Montaña resort has a fine dining room.