Complex sentence: In 1835, the first railroad of the European continent was built within the Flemish Diamond, between Brussels and Mechelen, the next year continued to Antwerp, and less than two decades later connected to France, Germany and the Netherlands.
Split into simpler sentences: In 1835, the first railroad on the European continent was built within the Flemish Diamond between Brussels and Mechelen. The next year it was continued to Antwerp and less than two decades later was connected to France, Germany and the Netherlands.