Today we're going to discuss the history of the bicycle. The first two-wheeled vehicle, called the draisine, was invented in 1817 by Karl von Drais. It had no pedals, so riders pushed their feet against the ground. In the 1860s, pedals were added to the front wheel, creating the velocipede. However, it was uncomfortable due to its rigid frame. By the 1880s, the 'safety bicycle' with a chain drive and equal-sized wheels became popular. Interestingly, the bicycle's popularity declined after cars appeared, but it saw a revival in the 1970s for environmental reasons.