Around eight centuries before the 24th century, ancient Bajorans used solar-sail lightships to travel beyond their own system, apparently as far as Cardassia.
Bajoran legends told of ancient explorers who crossed space in small ships driven by solar winds. Cardassian scholars dismissed the stories as fables, insisting that such fragile craft could never reach another star system.
In 2371 Benjamin Sisko built a lightship from ancient designs and set out with his son Jake. Caught in a tachyon eddy, the little ship was pushed to warp speed and carried into Cardassian space. Soon afterwards the Cardassians announced the discovery of the wreck of an ancient Bajoran solar vessel on Cardassia, conceding that the voyages had taken place.