Wonders of the world

Galápagos Islands, Ecuador

The giant Galápagos tortoise (above, a tortoise near the rim of the Alcedo Volcano) is one of the many species on the Galápagos Islands that are found nowhere else on Earth.

But these unique species "are in considerable danger from irresponsible visitation by large cruise ships and inappropriate development," Tourtellot said.

Though the islands' rating on National Geographic's Destination Scorecards has improved slightly in recent years, the area is "still very much on the cusp," he said.

"When you visit the Galápagos, make sure you're doing that with a responsible tour operator."

The volcanic archipelago, about 600 miles (965 kilometers) west of mainland Ecuador, was named one of the 28 finalists in the New7Wonders of Nature contest on July 21, 2009.

Dead Sea, Israel and Jordan

The Dead Sea (above, a boater rowing in Israel and Jordan, has received low ratings on past Destination Scorecards, Tourtellot said.

The sea is one of 28 finalists in the New7Wonders of Nature contest, announced July 21, 2009.

When the final cut is made in 2011, the new world wonders may either be overrun with damaging tourism or become better-managed destinations, Tourtellot said.

"It depends on the stewardship ethic in those places. In New Zealand the stewardship ethic is high. In Abu Dhabi it's totally clueless, and you've got everything in between."

Halong Bay, Vietnam

Halong Bay is home to idyllic islands and floating villages of fishers who ply the shallow waters for more than 200 species of fish.

The bay has become a popular tourist attraction and was named one of 28 finalists for the New7Wonders of Nature contest, announced on July 21, 2009.

Yet the 600-square-mile (1,553-square-kilometer) bay will get a "lousy score" on the National Geographic Center for Sustainable Destinations 2009 Destination Scorecard, an annual listing of the world's best preserved tourism spots, Tourtellot said. The 2009 list will be released in October 2009.

"A lot of the problem is in a heavily trafficked tourist area in one section and irresponsible development on the shoreline [that's] really messing it up," Tourtellot said of Halong. "Once you get away from that area, it's really nice."