What causes sinkholes to suddenly appear?

Sinkholes appear when underground voids form due to the erosion of soluble rock, such as limestone, by water. When the surface layer can no longer support its weight, it collapses, creating a sinkhole. Factors like heavy rainfall, excessive groundwater pumping, or construction can trigger their sudden appearance. Sinkholes can range in size from small depressions to massive craters, posing risks to infrastructure and ecosystems.