Photograph by Randy Olson, National GeographicThe rebuilt gates and mud-brick walls around the ancient city of Nineveh, near modern-day Mosul, Iraq, are popular tourist attractions.
Nineveh was the capital of the Assyrian Empire from 705 to 612 B.C., but the city was reduced to rubble by attacks from Medes, Babylonians, and Susianians. Archaeologists found the "lost" city in the mid-19th century and began excavations and reconstructions.
Still—like many of the sites on the Global Heritage Fund list—Nineveh suffers from the pressures of modern society. "At site after site after site, you are losing half the site to new development, encroachment, [and] you're getting looting of the site," the group's Morgan said. "We are not even talking about natural disasters."