Alpheus, a river deity, fell in love with Arethusa and pursued her until she was transformed into a spring. Poets invoke Alpheus to symbolise relentless desire and the merging of natural elements. His myth blends geography with romance, offering rich imagery of flowing waters and transformation.

Alpheus embodies the passionate pursuit theme central to many Greek river god myths, wherein divine beings chase nymphs who seek to preserve their virginity. His relentless pursuit of Arethusa across land and sea until she transforms into a fountain represents the overwhelming force of desire that cannot be denied. According to myth, Artemis transformed Arethusa into a spring, but Alpheus, changing into a river, mingled his waters with hers, achieving eternal union. This myth was particularly celebrated in Sicily, where the spring of Arethusa at Syracuse was believed to be connected to the Alpheus river in Greece. For students of pastoral poetry and Renaissance literature, this story provides rich material for exploring themes of metamorphosis, escape, and the boundaries between consent and pursuit. The myth influenced countless poets including Shelley and has been interpreted as representing both romantic persistence and problematic obsession.