To catch the action at the next waterfall on our list, you'll have to watch the seasons. Balaifossen is a winding, 2,510-foot (765-meter) waterfall located near the Osafjord in Ulvik, Norway. During warmer months, the narrow cascade slows to an imperceptible trickle; visit this waterfall in July, and you may spend your trip staring at a dry rock channel.
Balaifossen's temporal nature comes from its source. The waterfall feeds on melting snow from higher up in the region's mountains. Consequently, its appearance, flow rate and overall drama can vary greatly from season to season and year to year. A warmer-than-normal year could see the falls shrink from their normal course width of about 20 feet (6.1 meters) to a mere dribble. And while the waterfall currently stands as one of the tallest in Europe, its very existence could be uncertain if climate change reduces the region's average snow pack below the level needed to feed the falls [sources: World Waterfall Database, Law].