Palmyra's Arch of Triumph: the making of a London replica – video

Destroyed by Isis in October 2015, a 2000-year-old arch from Syria, has been meticulously recreated through 3D printing and installed in Trafalgar Square. The Guardian was given exclusive access to the design, build and installation of the 6-metre (20ft) marble model in Italy, before Boris Johnson unveiled the defiant recreation of the monument in London. Photograph: EPA/Will Oliver