As Europe's rivers recede during periods of drought, long-hidden traces of the past have resurfaced. Hunger stones, as they’re called, are riverbed boulders that usually stay underwater and hidden but become exposed when river levels drop significantly during prolonged droughts. Unlike a high-water mark, which records the highest water level, the hunger stone marks the lowest. Some hunger stones bear lists of years, including 1616, 1746 and 1842. For people living along rivers, low water often created a host of problems. Drought not only meant crop failure, but barges carrying grain struggled to navigate shallow channels, and both caused hunger — hence the name of the stones. Hunger stones acted as a warning to future generations that they would have to endure famine-related hardships if the water should sink to the level where the stones could be seen.
