One of Puerto Rico ’s best-kept secrets is its wealth of adventure travel options. Novices and experts alike can find plenty of rewarding activities that will challenge their skills and immerse them in the island’s unparalleled natural beauty.
Discover the most remote part of El Yunque Caribbean National Forest  by bypassing the paved trails in El Yunque Recreation Center and hiking El Toro Trail , a primitive trail starting at Carretera 186, kilometer 10.6, that passes through Tabonuco, Sierra Palm, and cloud forests, offering spectacular views of the south coast. The arduous 2.2-mile trail connects with Trade Winds Trail , a 3.9-mile primitive trail that ends at the southern tip of El Yunque Recreation Center.
Hike, rappel, and body-surf your way through San Cristóbal Cañon , one of the biggest canyons in the Caribbean, located between Aibonito  and Barranquitas  in the Cordillera Central . Adventure tour operators San Cristóbal Hiking Tour and Acampa  offer guided expeditions into the canyon and provide all the equipment and expertise you’ll need. Thick with vegetation, the canyon is 4.5 miles long and 500–800 feet deep, providing a great place to test your mountaineering skills.
Puerto Rico  has the third largest underground river cave system in the world. The tamest way to witness this fascinating subterranean world is to visit Las Cavernas del Río Camuy  on the north coast. Explore Cueva Clara, featuring a 170-foot-high room thick with stalagmites and stalactites and an underwater waterfall. For a more adventurous exploration of the cave system, contact Expediciones Palenque  and test your rappelling skills.
Travel by boat at night over the choppy waters of Mona Passage and pitch a tent on uninhabited Mona Island, a semiarid subtropical island with 20 miles of coastline, most of which is vertical cliffs more than 200 feet high. Hike the island’s trails, where you can spot feral pigs and goats as well as the prehistoric-looking Mona Iguana, which grows up to four feet long. Snorkel or dive the crystal-clear waters that surround the island’s perimeter. Several local outfitters provide transportation and equipment.
Thanks to a modest fishing trade, Puerto Rico has some of the healthiest, most intact underwater reefs to be found in the Caribbean, which makes it ideal for diving and snorkeling. There are several world-class dive sites around Puerto Rico, but some of the most spectacular dive sites are at Culebra . Culebra is still off-the-radar for most of the tourism industry and as a result, the clear, clean waters around the island are practically untouched by tourism’s polluting by-products.
Is old-school surfing too tame for you? Step up the action by attaching a sail to your board and harnessing the wind for more go-power at Ocean Park Beach . Velauno  offers classes and equipment rental for first-timers, or tips and equipment sales for experienced kite-boarders.