NEMO's roof is a public square, open to anyone without going into the museum below. Renzo Piano set the building over the southern mouth of the IJ road tunnel, and the tunnel decided its shape. As the traffic slopes down under the water the roof slopes up, so the building looks as though it is lifting out of the Oosterdok. The highest point is thirty-two metres above the water.
The roof is not high enough for a wide panorama, so what you get is the harbour close up, with historic ships lying in the dock below. To the west the old town looks almost flat, because the centre averages about fifteen metres and building above forty metres is in principle not allowed inside the ring road. That is why the church towers stand out: the Zuiderkerk nearest, then the Oude Kerk, then the Westerkerk further west. It opened in 1997, and its green outer surface is copper patinated in the factory before it was fitted, so the building looked old on its first day.