Chiang Mai is in the critical documentation phase of its UNESCO World Heritage bid. After a field evaluation in August 2026, ICOMOS has requested 19 additional items covering technical details (cross-sections, construction controls, ancient water systems) and cultural-historical questions, with a deadline of 27 October 2026. No further site visits are planned—evaluation will be document-based only. Local authorities are simultaneously building public understanding of Lanna culture and heritage zones to ensure coordinated messaging and lay groundwork for a World Heritage Master Plan for sustainable urban management.