40 Trips To Change Your World
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The Sierra Club organizes weeklong eco-immersion trips on the island of St. John. Amid the dense rain forests of the Virgin Islands National Park, volunteers assist archaeologists in restoring trails and 18th-century plantations, and attend lectures on eco-living.
Trip Tip: Bring your snorkeling gear to explore Trunk Bay, which has a 225-yard underwater route marked with plaques identifying the different fish species.
Luxury Level: Although the two-bedroom beach cabins are rustic, volunteers have a stretch of white sand practically to themselves.
Sierra Club; 415/977-5500; sierraclub.org; $1,175 per person, all-inclusive; February 9-16 and 16-23.