Summary
The paper deals – especially from a technical point of view – with the virtual anastylosis of the Trajan’s Arch at the Circus Maximus in Rome, realized by the Soprintendenza Capitolina and the Department of Architecture at the University of Roma Tre. The working group combined experts in paleography, architecture, 3D tracking, mathematics and epigraphy. The paper describes the four phases of the project: 3D relief of about 100 fragments; production of a database; development of mathematical models; development of planimetric, altimetric and 3D models of the Trajan’s Arch.

Innovative VR tools and techniques
• The paper deals with the planimetric, altimetric and three-dimensional virtual reconstruction of a fragmentary monument through a database of the fragments and mathematical or mesh models, developed with a Hexagon 3dReshaper software
• The 3D model of the reconstructive hypothesis of the Trajan’s Arch was exported in Collada format to use it in the AR environment
• The planimetry of the Trajan’s Arch is used as a marker to ‘project’ on the screens of hand-held devices the 3D virtual reconstruction of the monument

VR in education
• 3D reliefs of about 100 preserved fragments, both large and small, are used for the virtual anastylosis of a lost monument
• AR is used for both the examination of the hypothetical reconstruction and to communicate the results of the research through hand-held devices