The paddle wheel of a pedalo is a smaller version of that used by a paddle steamer. A two-seat pedalo has two sets of pedals, side by side, designed to be used together. Some models, however, have three pedals on each side to allow a person boating alone to pedal from a centrally seated position.
Pedalos, being particularly suited to calm waters, are often hired out for use on ponds and small lakes in urban parks.
The earliest record of a pedalo is perhaps Leonardo da Vinci's diagram of a paddle-powered craft driven by two pedals.