The River Amphryssos is located in Thessaly.
In Callimachus' "Hymn to Apollo" (48) Apollo tends Admetus' herds by the Amphryssos during his punishment for killing the Cyclopes. In the Argonautica (I.53) of Apollonius of Rhodes Eupolemeia bore the Argonaut Aethalides to Hermes near the Amphryssos.