A trein is a train. The first railroad in the Netherlands was opened in 1839, between Amsterdam and Haarlem. Other railroads quickly followed and by the end of the 1800s, passenger travel by rail had supplanted travel by barge. Many emigrants leaving through the ports of Rotterdam, Amsterdam, or Antwerp took the train to the harbor.
About Yvette Hoitink
Yvette Hoitink, MLitt, CG®, QG™ is a professional genealogist, writer, and lecturer in the Netherlands. She has a Master of Letters in Family and Local History from the University of Dundee, and holds the Certification of Genealogist and Qualified Genealogist credentials. Yvette served on the Board of Directors of the Association of Professional Genealogists and won excellence awards for her articles in the National Genealogical Society Quarterly and the Association of Professional Genealogists Quarterly. Yvette has been doing genealogy for over 30 years. She helps people from across the world find their ancestors from the Netherlands and its former colonies, including New Netherland. Read about Yvette's professional genealogy services.
Is there a link to find these maps online?
I found this particular map on Wikimedia. I don’t know of any websites specializing in Dutch railroad maps.