The man in the orange jacket let us in to the stairs down.
Last week when we were walking in Amsterdam we saw at a tramway-stop people vanishing in the ground entering the two red towers at the first photo. It was so strange, we went for a look where they had gone.
It appaered it was possible to visit the work in progress of the new underground. You could go down with several iron stairs and suddenly their was a little viewpoint to have a look at man working in the deep.
It was so weird, one moment you're walking in a crowdy shopping street, the next you are looking in a complete different world under the same street and then your're in the street again.
It was a kind of a Alice in Wonderland experience, or Harry Potter.