Culture heritage conservation is necessary to produce the initial technical documentation. This one provides plans that help in using the best approaches to protect culture heritage. Images are considered as an important source of data required to achieve this documentation, where they can be used to extract semantic and 2D-3D geometric data. In case of large planimetric objects, we can use the controlled mosaics as source of these data. In the present study, instead of using professional photogrammetric software, we propose an alternative solution to document the large planimetric historical objects. This approach is based on producing a mosaics from a group of digital rectified photos by using some capabilities of a GIS that are originally applied to produce mosaics from overlapped maps. The produced mosaic well then be used as semantic and geometric documentation source in this GIS. Geographic Information System facilitates largely the conservation, development and renovation process of historical areas. To ensure the validity of the resulted mosaics, we will compare it with a mosaics calculated from the same photos by using a professional photogrammetric software.