After the Argonauts got through the clashing rocks, they entered the Black Sea and discovered the island Thynias. As they approached the island, they saw Apollo flying overhead in his sun chariot to visit a mythical people called the Hyperboreans, descendants of Boreas’ daughter, Khione. The island shook when he passed so the argonauts decided to build Apollo an altar and shrine, just to avoid offending other gods. Based on every other Greek myth I’ve ever read, that was a super good call.
Their next stop was the river Acheron, which flows into Hades and here they met King Lycus. The king was friendly and offered to let them rest as his place, but tragedy struck when their prophet was killed by a wild boar, and a minor Argonaut is killed by an illness. They build a memorial and with heavy heart they sailed on.
As they sailed away from the Acheron, they notice Sthenelus, a deceased comrade of Hercules who was left behind after Hercules completed his labor to steal Hippolytas’ girdle, and three living humans who were stranded at the island of Sinope. The Argonauts help the ghost Sthenelus find peace and welcome the three living guys on board. To collect them, the Argonauts have to make a brief stop on an island of Amazon influence, but skedaddled before the women could organize and attack them.
That’s right, the Amazon’s were so epic the Argonauts ran away.