During the last twenty years, the Baekdudaegan – a transnational mountain range stretching across the Korean peninsula – has gained importance both as an ecological corridor and as a performative symbol of a Korean collective identity. This presentation analyses how narratives and conservation projects regarding the Baekdudaegan are seen as means of emancipation from the colonial geographical knowledge of Korea. In a theoretical perspective, my work examines the process by which geographical objects are politically and socially constructed, and how they – or their representations – can become symbols and emblems of identity and frames of action. First, I explore how the perception of this mountain range has changed over time from an important cosmological figure to an ignored object in twentieth century science. Since the importation of Chinese geomantic theories in Korea during the seventh century, mountain ranges have been seen as arteries that conduct telluric and spiritual energies throughout the peninsula, the Baekdudaegan being the backbone of this organic system. Japanese scientists then brought a new modern and scientific understanding of the peninsula, notably influenced by German geomorphologists, when Japan annexed Korea around 1910. The new carving of the Korean territory effectively disrupted geomantic environmental knowledge, erasing the Baekdudaegan from Korean maps and minds, until amateur cartographers and hikers start lobbying for its revival in the early 1990s. Secondly, using discourse and arguments analysis, I examine how different contemporary stakeholders use the Baekdudaegan in various post-colonial narratives and environmental conservation projects. On the one hand, pro-reunification narratives use the mountain chain as a natural proof of the unity of the Korean peninsula. On the other hand, it is perceived by certain scientists and environmentalists both as a means to de-colonize environmental knowledge and seen as a tangible indigenous heritage that can lead to reunification.