San Cristóbal Hiking Tour (P.O. Box 678, Barranquitas, 787/647-3402, walimai [at] hotmail [dot] com, http://barranquitaspr.org/viajes [1]) offers a variety of weekend excursions in San Cristóbal Cañon [2] from moderate hiking and biking tours to extreme rappelling and mountaineering tours. It also offers tours to Bosque Estatal Toro Negro and other natural sights in the area. Prices range $50–140, depending on the excursion and the number of people in your party.
Acampa (1211 Ave. Piñero, San Juan, 787/706-0695, info [at] acampapr [dot] com, www.acampapr.com [3]) offers rappelling and rock-climbing tours into San Cristóbal Cañon [2] for experienced adventure travelers. Explore the canyon’s waterfalls and river. Acampa also sells and rents camping, hiking, and mountaineering gear at its store in San Juan [4].
Links:
[1] http://barranquitaspr.org/viajes
[2] http://www.moon.com/destinations/puerto-rico/cordillera-central/aibonito-and-barranquitas/sights/san-cristobal-canon
[3] http://www.acampapr.com
[4] http://www.moon.com/destinations/puerto-rico/san-juan