Adapting a Cluster-Based Framework for Digital Shipping Corridors: An Exploratory Case Study of the Helsinki–Tallinn Corridor

European maritime transport is undergoing a profound transformation driven by the dual imperatives of decarbonisation and digitalisation. Although green and digital shipping corridors are increasingly promoted as mechanisms for supporting this transition, there remains limited understanding of how digitalisation and sustainability can develop in parallel in cross-border maritime systems. This study adapts an existing cluster-based smart port framework to the corridor level to examine digital shipping corridors as integrated socio-technical systems. The framework is structured around four dimensions: technological foundations, intelligent port systems, performance-focused digitalisation, and strategic governance and sustainability. A qualitative case study based on publicly available documents and secondary sources is used to illustrate the framework and examine how these dimensions are reflected in practice. The findings indicate that the corridor demonstrates significant progress towards digital integration at the port-terminal level, although full corridor-wide integration remains incomplete. At the same time, the analysis highlights ongoing challenges related to broader system integration and the transition towards zero-emission maritime transport. The study concludes that digital shipping corridors should be understood as evolving socio-technical systems whose development depends on the alignment of technological innovation, governance capacity, and sustainability objectives. The study demonstrates how cluster-based analysis can be operationalised through qualitative case-study research. The proposed framework contributes to adapting smart port research from individual ports to corridor-level systems and offers a basis for future comparative research on maritime transport transitions.