TONY CRADDOCK / SCIENCE PHOTO LIBRARY TONY CRADDOCK / SCIENCE PHOTO LIBRARY
Frozen waterfall. Still or slow-moving water freezes more easily than fast-flowing or turbulent water, but if temperatures are low enough then even large rivers and waterfalls will start to freeze, though some water may continue to flow below and behind the ice. Photographed in Alberta, Canada.
Model release not required. Property release not required.