Ocean World, Calle Principale 3 at Cofresi (tel. 809/291-1000; www.oceanworld.net), is the largest entertainment complex in the country, lying 5km (3 miles) west of Puerto Plata. It combines a plush casino and a world-class marina with such mass market venues as a kiddie park and an aquarium for marine life. There is a series of watery "pens" and habitats for the care, feeding, and display of dolphins, sea lions, sharks, stingrays, piranhas, and other denizens of the Amazon rainforest. A number of close encounters with these nautical creatures, especially dolphins, is offered, but these encounters are not cheap, ranging from US$70 to US$250 (£35-£125) per person, depending on your age and the length of exposure you opt for. Supervision of these encounters is carefully monitored by trainers, and reservations are recommended. For those 13 and up, admission is US$55 (£28), lowered to US$40 (£20) for ages 4 to 12 and free for those 3 and under.
Fort San Felipe, the oldest fort in the New World, is a popular attraction (tel. 809/261-6043). Philip II of Spain ordered its construction in 1564, a task that took 33 years to complete. Built with 2m-thick (6 1/2-ft.) walls, the fort was virtually impenetrable, and the moat surrounding it was treacherous -- the Spaniards sharpened swords and embedded them in coral below the surface of the water. The doors of the fort are only 1m (3 1/4 ft.) high, another deterrent to swift passage. During Trujillo's rule, Fort San Felipe was used as a prison. Standing at the end of the Malecón, the fort was restored in the early 1970s. Admission is 75¢ (40p), free for children 11 and under. It's open daily 8am to 5pm.
Isabel de Torres (tel. 809/970-0501), an observation tower that was heavily fortified during the reign of Trujillo, affords a panoramic view of the Amber Coast from a point near the top, 780m (2,558 ft.) above sea level. You reach the observation point by teleférico (cable car), a 10-minute ascent. Once here, you're also treated to 3 hectares (7 1/2 acres) of botanical gardens. The round-trip costs RD$250 (US$7.50/£3.75) for adults, RD$100 (US$3/£1.50) for children ages 12 and under. The aerial ride runs Thursday to Tuesday 8am to 5pm. There's often a long wait in line for the cable car, and at certain times it's closed for repairs, so check at your hotel before you head out.
You can see a collection of rare amber specimens at the Museo de Ambar Dominicano (Museum of Dominican Amber), Calle Duarte 61 (tel. 809/586-2848), near Puerto Plata's Central Park. It's open Monday to Saturday 9am to 6pm. Guided tours in English are offered. Admission is RD$40 (US$1.20/60p) or RD$7 (20¢/10p) for children.