Crowdsourcing for 3D Digital Modelling: Ioannina City-Chairedin Pasha Sarai Case Study.

Nowadays, billions of photographs are available on the internet, under an open-access/open-data status, thus forming the largest and most diverse collection of optical data ever assembled. These images can be easily recovered, and digitally processed for the photogrammetric restoration of monuments, partly or completely destroyed, thus rendering clear the effective contribution of crowdsourcing under the perspective of restoring our cultural past. This is the case of the lost landmark of Chairedin Pasha Sarai in Ioannina city, Greece: the extensive scientific research on the building complex’s location, form and dimensions aiming to the respective 3D digital model design and development, has been further creatively supported and supplemented by downloading from the internet and making use of several photographs depicting different aspects of the building, at various chronological periods, before its final complete destruction, thus allowing the visual 3D digital restoration of the landmark, as well as its interaction with the surrounding urban web and its successive alterations. In this context, the crowdsourcing dimension might be considered as a basic element, a catalyst, for the restoration of cultural heritage, while the active participation of society in matters of culture, as is the contribution in monuments’ documentation procedure, awakens the collective consciousness in the direction of the protection, preservation and highlighting of cultural heritage.