The remains of the temple of Mithras were excavated in the 1950s during the redevelopment of the Walbrook site in the City of London and attracted significant public interest. The stone and brick masonry remains were removed following detailed recording and a version of the temple was recreated in the 1960s on a nearby site above a car park. Recent redevelopment of the site provided the opportunity to return the temple remains to their original location and to create a more accurate reconstruction, faithful to the drawn and photographic records of the 1950s. The process of dismantling the 1960s version of temple and planning and reconstructing the “ruin” was a multi-disciplinary project, with input from archaeologists, conservators, architects, engineers and the statutory authorities. The remains are now open to the public and form part of a larger interpretive exhibition within the new Bloomberg building in the city of London.