This approach is consistent with the reality that it is frequently not possible to preserve all archaeology in situ. In such cases preservation by record is internationally recognised, and also accepted by Dúchas, as an appropriate method of preserving the archaeological heritage. In the event, and to discharge the conditions imposed by the EIA approval, the National Roads Authority and Dún Laoghaire-Rathdown County Council have commissioned extensive archaeological investigations and excavations at the Carrickmines site. These have so far been running for two years and extended – from an earlier estimate of ten months – to deal with the greater than foreseen complexity of the site. Up to 200 archaeologists have been employed on site and the current running cost of the work comes to some €6 million. This work has already significantly enhanced the national archaeological record and recovered more than 40,000 artefacts as an enduring legacy for this and future generations to appreciate and learn from. Thanks to the substantial investment of resources by the road authorities, more has been done to improve our knowledge and understanding of the Carrickmines archaeological heritage in the past two years than in the previous 350, during which it lay buried.