Seven years of civil engineering for the LHC

Although preliminary civil engineering for the LHC project was taking place even before construction of the LEP, it can be considered that the project was fully underway in 1995 when the market surveys and calls for tenders for the engineering consultancy firms were launched. This paper traces the development of the project from these early days to the current situation whereby almost 70% of the civil engineering works are completed. The paper will illustrate and compare some of the changes that have taken place in the project as it has progressed from preliminary layouts drawn up in-house at CERN through the design phase carried out in conjunction with external consultancy firms and finally into the construction phase which is currently ongoing.