Sri Lanka's post-pandemic tourism recovery has renewed pressure on cultural heritage destinations to reconcile visitor growth, revenue generation, authenticity, community interests, and physical conservation. This study examines that governance problem in the Cultural Triangle by retaining the original mixed-method design, which included a quantitative tourist sample of 384 participants and qualitative engagement with local communities, Department of Archaeology officials, and Sri Lanka Tourism Development Authority managers. The original thematic and SPSS-based quantitative analyses were supplemented by verified secondary statistics from national tourism and Central Cultural Fund records. International arrivals increased from 719,978 in 2022 to 2,362,521 in 2025, while Central Cultural Fund sites recorded 1,974,888 visits in 2025 and Sigiriya alone accounted for 55% of that total. The integrated evidence indicates that tourism growth is concentrated at a small set of heritage nodes, while authenticity, community participation, and conservation capacity require stronger institutional protection. The study proposes a governance framework combining conservation thresholds, community co-governance, timed and data-informed visitor management, transparent conservation-linked revenue governance, augmented and virtual interpretation, and heritage digital twins. The framework reframes tourism success from volume maximization toward conservation-conditioned value creation and provides a practicable basis for aligning tourism development with long-term cultural heritage stewardship.