

Tunnelling in Greece has shown a remarkable development in the last 20 years and this is due to the real “cosmogony”, which was occurred during the aforesaid period, in the infrastructure projects. Indeed, since the early 1990's and until even recently, a very large number of motorway and railway projects (i.e. Egnatia Motorway, Motorways Concession Projects, Athens and Thessaloniki Metros, ERGOSE railway lines, etc.), either were fully constructed or are in the stage of their completion. As a consequence, significant design and construction experiences, which are related directly to the tunnels' excavation schemes, primary support measures and different types of final lining (i.e reinforced, lightly reinforced or unreinforced) in a wide variety of geological / geotechnical conditions, were gained. The obvious merit from all these experiences, is that if they will be applied within reasonable frameworks of application, can offer significantly to the necessary tunnels designs' optimisations and to the rationalisation of the corresponding tunnels' construction costs. The future of tunnelling in Greece seems promising through new financing models (i.e. concession agreements), since one of the obvious mid-term “antidote” to the economic recession is the investment to the construction of new but necessary infrastructure projects. Some of these new projects are the extensions of Athens and Thessaloniki Metros, new urban and suburban motorways and new railway lines.