Today, with the increasing role of tourism in the urban economy, garden cities as unique destinations require strategic planning based on sustainability and competitive advantage. However, the lack of a coherent management model in Marand urban management has presented serious challenges to the optimal utilization of the natural and historical capacities of this region. The present study aims to determine the prioritization model for sustainable tourism development strategies in Marand Garden City with a competitiveness approach. This research is applied-developmental in terms of its purpose and descriptive-analytical in nature, which has been implemented with a mixed approach (qualitative-quantitative) in seven steps. Data collection was carried out through documentary studies, semi-structured interviews with 12 experts in the field of tourism and urban management, and the Delphi technique (four rounds). Data analysis was carried out at four levels, including content analysis of interviews, structural analysis with MICMAC, structural-interpretive modeling (ISM), and scenario planning with the CIB technique. The findings showed that out of 32 identified factors, 10 key drivers including economic security-e-commerce, ecological diversity, health and wellness infrastructure, economic environment and infrastructure, international relations, transportation infrastructure, hotel services, price competitiveness, travel industry attractiveness, and cultural-historical resources play the most role in the system. ISM modeling identified integrated destination governance and conservation of gardens and basic resources as fundamental drivers. The final prioritization of strategies was determined in three time horizons: in the short term, establishing integrated management and protecting the garden city identity; in the medium term, smartening and empowering the local community; and in the long term, branding and establishing international competitiveness. The conclusion shows that the proposed model emphasizes “development from the ground up” and considers the realization of integrated governance and the protection of Marand’s unique assets as essential prerequisites for achieving sustainable competitiveness.