Pagasai was the location from which Jason and the Argonauts set sail and is featured heavily in the eponymous poem by Apollonius of Rhodes. The city also enjoyed numerous springs in its vicinity.
Philip II later conquered the city during his battle against Onomarchos in the Sacred Wars. In roughly 290 BCE, Demetrios I Poliorketes moved all the inhabitants to his newly founded namesake city of Demetrias, though the city was refounded some time afterwards.
It still existed during the time of Strabo, who listed it as the port of Pherai.
I find it interesting that the coin depicts Philoktetes instead of Jason, but I guess this makes some sense since Philoktetes was associated with Thessaly, and thefore may have been involves in a story at Pagasai.
Demetrias founded by Demetrios I Poliorketes, who moved the inhabitants of Neleia, Pagasai, Ormenion, Rhizos, Sepias, Olizon, Boebe, and Iolkos to create it.