Croatia's Puzzling Village of Sinkholes
Vedrana Simičević, BBC Future
It happened suddenly and without warning. Where there should have been the emerging first shoots of potato seedlings behind the orchard in Nikola Borojević's spacious garden, there was now huge hole. Measuring 30m (98ft) wide and 15m (49ft) deep, it quickly filled with water. And it wasn't the only one.