Fit Travel: Top 10 Adventure Trips For a Good Cause

Iceland is a literal hotbed of seismic activity and magma flow. Through Earthwatch Institute, you can help create maps documenting the minor disturbances volcanoes cause beneath the earth's surface, essentially giving scientists a heads-up on possible future eruptions. From the glacier-capped Vatnajökull volcanoes in the south to the ever-active Krafla volcano (one of Iceland's most spectacular) up north, you'll tramp across flat flood plains and lunar-like landscapes recording your finds.

You Need: 7-14 days. ($1500; govoluntouring.com)