Hearing is one of our most pervasive senses. There is no equivalent to closing our eyes, or averting our gaze, for the ears. When we think about great architectural achievements in European history, such as ancient amphitheatres or Gothic cathedrals, their importance is strongly tied to their acoustic environment. The acoustics of a heritage site is an intangible consequence of the space's tangible construction and furnishings. Inspired by the project's namesake (Phé, for the constellation Phoenix), and the relatively recent fires at Cathédrale de Notre Dame de Paris and Teatro La Fenice opera hall, the PHE project focuses on virtual reconstruction of heritage sites, bringing them back from the ashes. In addressing the intangible acoustic heritage of architectural sites, three main objectives have been identified for this research project: Documentation, Modelling, and Presentation. In parallel, three heritage sites are participating as case studies: Tindari Theatre (IT), Notre-Dame de Paris Cathedral (FR), and The Houses of Parliament (UK). The acoustics of a space is immersive, spatial, and due to the nature of auditory perception egocentric, in contrast to visual perception of an object, which can be observed from "outside". Consequently, presentation methods for communicating acoustic heritage must represent the spatially immersive and listener-centric nature of acoustics. PHE will lead development of a museum grade hardware/software prototype for the presentation of immersive audio experiences adaptable to multiple platforms, from off-site immersive speaker installations, to mobile XR via smartphone applications.