Besonderhede van voorbeeld: 7710073745250647892

German

In der Zone Piora wurde 300 m über dem späteren Basistunnel ein 5 km langer Erkundungstunnel errichtet, um die geologischen Bedingungen zu testen.

English

In the Piora zone, a 5km long exploratory tunnel was constructed 300m above the later base tunnel level from which exploratory borings were drilled were down to verify the geological conditions on the level of the future Base-Tunnel.