As part of UNESCO’s multi-disciplinary team, ATA acted as heritage consultation expert for the preparation of a Comprehensive Conservation Management Plan (CCMP) for the Darjeeling Himalayan Railway. The project involved documentation, mapping, condition assessment, and conservation strategy development for the 19th-century mountain railway, recognized as a World Heritage Site. The work also included preparation of bespoke conservation manuals for railway staff to support long-term management of historic infrastructure. The project required extensive stakeholder consultation and the development of innovative methodologies for mapping and managing a complex heritage transport system in an active operational context.