Small islands in the Mediterranean Sea, although endowed with exquisite land and maritime natural and cultural resources, are in most cases lagging behind areas, mainly due to insularity. Through their long history, many of them are strongly interwoven to events of European or even global significance, e.g., World War (WW) I and II. Such events have left in their “bodies” important remains, largely conditioning their socio-economic trajectory. Preservation and sustainable management of this Cultural Heritage (CH) is, in this work, perceived as a two-sided coin, serving endurance of European identity, memory, and CH for future generations on the one side; and leveraging future cultural tourism trails of these disadvantaged areas on the other. The goal of this article is to ‘unbury’ land and maritime, tangible and intangible, cultural remains and use them to unveil heritage-led development paths of small Mediterranean islands. This is demonstrated through a specific case study, a distinguishable insular territory and WW II battlefield scenery, Leros Island, Greece; and is accomplished by a participatory spatial planning framework, embedding scenario planning, spatial data management, and e-participation technologies (Web-GIS, social networks) for community engagement. The latter is valued for assessing options available for an integrated, sustainable, and resilient exploitation of land and maritime CH; and raising awareness of local population as to the role of CH as enabler for the transition from past failures to more promising, culturally-driven, and locally-adjusted future development trails.