Himalayas, the world’s youngest mountain range is home to diverse ecosystems and cultural landscapes, attracting adventure enthusiasts, pilgrims, and tourists, seeking nature, spirituality, and recreation. However, escalating tourism pressure, rapid urbanisation, disaster vulnerability and climate change are growing threats to the ecology and well-being of the mountains. The study delves into the discourses and discussions of online communities regarding unsustainable tourism in the Indian Himalayas. Utilizing, netnography and qualitative data analysis methods, it uncovers key areas of concern and narrative surrounding tourism development in the region. The analysis takes evidence from two recent disaster events in 2023: the flood-landslide catastrophe in Himachal Pradesh and the land subsidence crisis in Joshimath, Uttarakhand. Leveraging collective behaviour theory, the findings uncover prominent themes in public discussions. Importantly, the findings decode the major apprehensions regarding tourism development in the fragile ecosystem. And, the study highlights the pressing need to address sustainable development in the mountains. Furthermore, the study attempts to decipher various theoretical and practical implications for policymakers and destination managers.