Necessity the mother of this one, too

The massive eruption of a volcano in 1815 led to the invention of the modern bicycle. Mount Tambora, a large volcano in present-day Indonesia, erupted, triggering extreme weather and harvest failures in many areas around the world. There was large-scale famine and starvation for horses and livestock. This disaster raised the question of how to transport people without horses. German inventor Karl Drais, right, worked on a propulsion device that could replace horse riding. Two years later he presented his invention — a two-wheeled contraption that came to be called a velocipede