Traditional settlements constitute part of the cultural heritage and their preservation is an important priority, acknowledged in the present study as a multidisciplinary, multi-scale and complex issue. This study quantifies the visual impact of traditional settlements in Cyclades that arise from structures which are considered to create pressure on the island landscape and negative visual impact. These structures disrupt the landscape continuity; they are both incongruous with the dominant local scale and incompatible with the forms and shapes that are appropriate on the Cyclades islands. This paper examines these issues in the context of the management of insular traditional settlements within the Greek spatial planning framework.

Unregulated built-up area expansion is a typical practice in Greece mostly on the islands, it is driven by the mass tourism development and the demand for second houses. Significant social, economic and environmental issues are linked to this practice. Santorini, a Greek island – which is characterized by important natural and cultural heritage properties and intense tourist development – is chosen here for the empirical part of the study. This paper attempts to study and quantify both the unregulated built-up area expansion and its impact on the natural and cultural environment. The intense ex-urban built-up area expansion that takes place on Santorini is interpreted on the basis of the Greek spatial planning framework so that its weaknesses that emerge will address the issue.

Cultural heritage serves as a repository of a place’s history and identity, integral to its landscape and central to all three sustainability goals. However, managing and protecting cultural heritage through regulatory planning often proves inadequate. This particularly applies to islands where infrastructure development pressures and urban sprawl lead to significant changes. This study quantifies the impact of uncontrolled built-up area dispersion on islands’ cultural heritage, focusing on the Southern Aegean region. By identifying and delineating the boundaries of archaeological areas and historic sites, we assess pressures through the mapping and quantitative analysis of built-up areas derived from the Global Monitoring for Environment and Security (GMES) program. The results reveal spatial relations and potential conflicts, underscoring the insufficient protection of cultural heritage due to inadequate management and ineffective planning tools. Specifically, on islands like Mykonos and Naxos, over 80% of their archaeological areas are impacted by urban sprawl. Additionally, this study finds that six islands (Antiparos, Irakleia, Kea, Mykonos, Paros and Patmos) have over 60% of their built-up areas in exurban regions, exacerbating pressures on heritage sites. These findings highlight the need for an integrated spatial planning system that incorporates landscape and cultural heritage assets into strategic planning regulations, ensuring the preservation of these essential resources amidst ongoing development pressures.