This article explores the symbiotic relationship between nature and poetry, which is in many ways pivotal for Vergil’s Arcadia, as an imaginary construct. Interdependence of the ideal landscape and the poetic creativity finds an especially refined and polysemic expression in the fagus, which functions in the Eclogues simultaneously as a literary image, a metaphor, and a symbol. It is also strongly reminiscent of the proto-idyllic segment of Plato’s Phaedrus (230b-e), describing a beautiful πλάτανος that turns out to be the source of anagogic inspiration. Based on this analogy, a comparative reading of Plato’s dialogue and Vergil’s idyllic poems is offered, and the ascensus motive of Eclogue 5 reveals the Platonic echoes. The anagogic aspect of Arcadia is examined from an intertextual and interdisciplinary point of view, hopefully contributing to seize the polyphonic complexity of Vergil’s poetics.