At least seven hues of blue and turquoise make this freshwater lagoon unique.

The only castle in North America to ever house European sovereigns.

A uniquely robust and historic look at Mexico's omnipresent dance with Death.

Every equinox this Maya pyramid puts on a spooky ancient light show.

The world's most elegant power lines.

The final resting place of the great navigator, or maybe his brother.

Founded as a refugee camp, now a popular tourist spot.

The world's longest known cave system.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

The stoutest tree in the world.