Hot air balloons have been around since at least 300 AD, but modern manned balloons only got off the ground in the 1700s. The concept is simple - the balloon or envelope is filled with air which is heated making the particles zoom around faster and creating more space between them. This makes the hot air less dense and heavy than the surrounding air, and thus it rises. The pilot can control when the balloon goes up and down and relies on predicting the wind direction at various altitudes to move horizontally. Amelia Nurse meets several passionate balloon pilots who tell her why they take champagne everywhere with them, explain some inventive uses for shaving cream, and ultimately try to convert her to the sport they're so nuts about.