Maastunnel

The Maastunnel is a tunnel in Rotterdam, the Netherlands, connecting the banks of the Nieuwe Maas. About 75,000 motor vehicles and a large number of cyclists and pedestrians use the tunnel daily, making the Maastunnel an important part of Rotterdam's road network. Building commenced in 1937 and finished in 1942. There was no official opening ceremony, but the Dutch held an unofficial opening ceremony in secret without Nazi participation.

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