It’s not just Venice. Climate change imperils ancient treasures everywhere.

Saltwater rushed into St. Mark’s Basilica in Venice last week, submerging marble tombs, intricate mosaics, and centuries-old columns. Last month brought the launch of the international Climate Heritage Network, a coalition of cities, tribes, businesses, universities, and other organizations that promise to recognize the harm climate change poses to iconic cultural places and harness “the power of cultural heritage for climate action.” Many UNESCO World Heritage sites have survived wars, floods, and other disasters over the course of hundreds and even thousands of years. Archaeological ruins in Tanzania : At a 13th-century trading center called Kilwa Kisiwani, on a small island just off Tanzania’s coast, merchants handled a good chunk of the trade in the Indian Ocean — gold, perfumes, porcelain, and more — and spread Swahili culture far and wide. : At a 13th-century trading center called Kilwa Kisiwani, on a small island just off Tanzania’s coast, merchants handled a good chunk of the trade in the Indian Ocean — gold, perfumes, porcelain, and more — and spread Swahili culture far and wide. The Orkney Islands off Scotland’s north coast contain some of the oldest sites in the world, with some structures built around 5,000 years ago, before the Great Pyramid of Giza.