For a new Area in Amsterdam , "de Houthavens" Paul de Kort and Thijs Verburg designed 8 bridges for cars and 3 bridges for pedestrians. In the top of the pillars of the bridges they wanted something that resembled the ice of the Permafrost. The Eridanos/ Baltic river is the former river that must have run through what now is called the Baltic sea. the Eridanus started 40 milion years ago, 12 milion years ago it reached the Nothsea and it created with its sediment an enormous Delta. In the Bavel Interglaciaal is must have had a lenght of 4200 km.
The wood that used to come in through the Houthavens ( the wood harbour) came from the Baltic states.