For years, even the mere mention of the idea of building a new metro line had been taboo. The extensive demolition of buildings that went along with the construction of the existing metro line in the 1970s led – quite understandably – to a great reluctance and major opposition to the building of a new metro line. 
  
But time hasn’t stood still. In the meantime, the underground tunnel-boring techniques have advanced so far that it is now possible to bore a tunnel even in soft ground like that under Amsterdam.

There are great advantages to boring a tunnel. No houses need to be demolished, and the street doesn’t need to be broken open.

The logistics can be carried out from a single location (the water of the Damrak). Moreover, the method is quick in comparison to digging a tunnel from the ground level: the tunnel-boring machine covers an average of 10 to 15 metres a day and works continually, day and night.