In this study opera serves as a nexus, shedding light on the circulation of ideas about politics, nature, technology, and aesthetics. Morris investigates operatic representations of the mountains in German modernism, showing how the liminal quality of the landscape forms the backdrop for opera's reflexive engagement with the identity and limits of its constituent media. This operatic reflexivity invites consideration of musical encounters with mountains in other genres, and Morris shows how these issues resonate in Strauss's Alpine Symphony and in the Bergfilm. By using music and the ideology of mountains to illuminate aspects of each other, Morris makes an original and valuable contribution to the critical study of modernism.