furthermore, according to pliny the elder and his citation by gaius julius solinus, the sea voyage time crossing the gorgades (cape verde islands) to the islands of the ladies of the west ("hesperides", actual são tomé and príncipe and fernando po) was around 40 days: this fact has created academic discussions about the possibility of further roman travels toward guinea and even the gulf of guinea. a roman coin of the emperor trajan has been found in congo.