Trikka received its name from Trikka, who was a daughter of Pineios and is depicted on this coin. Pineios in turn was a river god who once turned Daphne into a Laurel tree in order to escape from Apollo.
Homer listed Trikka as the kingdom of two sons of Asklepios, and a temple to him was long in the city. According to Strabo, it was the greatest in Greece, so even more important than those at Epidauros and Kos, though that may have been a function of the times.
Interestingly, when Alexander the Great allowed all exiles to return to their home cities, Trikka was one of two (the other being Pharkadon) that were excluded, although we have no idea why.
The modern city of Trikala was built over Trikka, though there are a few traces of the ancient settlement that remain.