People are most familiar with bicycles built for a single rider since these are the most common, but Tandem Bicycles also have a loyal following. There are bicycles for use on roads and on trails as well. They can be fun, but obviously the riders have to trust one another and be able to work together. This is especially true of the stoker, who rides in the back seat and has to rely on the captain to accurately steer the bike.
USA Cycling also offers some racing categories for tandems, if you’ve got a need for speed. These also provide a way for blind athletes to compete in bicycle racing. The blind rider sits in the back seat to provide extra power to the pedals while the front rider, who can see (this is very important!), provides the steering.