Pennsylvania hides an underground river that continues far beyond what anyone has mapped, shrouded in mystery.

Satellites are giving scientists a powerful new way to watch over the world’s bridges. Using radar imaging, researchers can detect millimeter-scale movements that may signal early structural problems ...

If someone told you there’s a tunnel in Virginia that’s 850 feet long, 10 stories high, and carved entirely by water, you’d ...

But hiding along a stretch of Interstate 90 in Central Washington is a geological marvel that rivals anything you’d find on ...