There are watersports kiosks about every 90m (300 ft.) along the beach, any of which will rent you snorkeling gear and tell you the best spots for seeing fish. You can also rent sailboats, windsurfers, and other watersports gear at any of the kiosks.
Gipsy Ranch, Carretera Sosúa-Cabarete, opposite the Coconut Palm Resort (tel. 809/571-1373), is the region's largest and best-recommended riding stable, home to about 20 horses, which can be hired for equestrian treks of between 1 and 4 hours. You'll begin your experience at the stone corral about 7km (4 1/2 miles) from Sosúa and 5km (3 miles) from Cabarete. A 1/2-hour jaunt goes for RD$448 (US$13/£6.70); a 4-hour excursion through forests and along beaches costs RD$1,596 (US$48/£24). Reservations are strongly recommended.
Many divers are attracted to the waters off Sosúa. In town the best outfitter is Northern Coast Diving, Calle Pedro Clisante 8 (tel. 809/571-1028; www.northerncoastdiving.com). There are more than a dozen diving sites off the coast, including a wreck, a canyon dive, and a wall dive. Northern Coast offers PADI-certified divemasters or instructors, featuring a two-tank boat dive for RD$1,960 (US$59/£29) with equipment, RD$1,680 (US$50/£25) without. For RD$9,800 (US$294/£147) you get 3 days of diving and certification training. The outfitter also offers 3-hour snorkeling excursions for RD$1,120 (US$34/£17) per person.
Several adventure tours are offered by El Tour Tours, corner of Calle Dr. Alejo Martínez and Calle Duarte (tel. 809/571-4195; www.eltour.net), founded in 1999. River rafting is an exciting pastime costing RD$1,820 (US$55/£27). They can also arrange horseback riding for RD$896 (US$27/£13) and catamaran sailing for RD$2,100 (US$63/£32).