By accident a 16th century map of the Netherlands has been discovered. This printed map not only presents the oldest reliable map image of the Southern Netherlands, but also sheds a light on the incomplete copy of the oldest known map of the whole Netherlands.
On the verso of a copy of Dese corte cronikel (Utrecht, Hendrick I van Borculo, 1586), now in the possession of the Royal Library in Brussels (via the antiquarian book dealer Plantijn in Breda), is printed a woodcut map. It was pasted on a piece of paper and therefore hardly visible. Some months ago, a restorer of prints managed to loosen the map from the paper. It became clear that the map has been made by Hendrick I van Borculo's father, the Utrecht-based publisher Herman van Borculo, from 1557.
The map is oriented to the south-east and covers the region from Calais (France) to Trèves (or Trier, Germany) in the south and from Vlieland to Marburg (Germany) in the north. The map is a copy of one from 1526 of the Baltic and North Sea by the Antwerp-based publisher Jan van Hoirne. That map is considered as the oldest printed map of the Netherlands, of which only one incomplete exemplar is known. With this discovery, Van Hoirne's complete map can largely be reconstructed. It is likely the Van Hoirne map is part of a four-sheet wall map. The Van Borculo map also shows the oldest reliable map image of the Southern Netherlands, because these areas don't figure on the fragments of the Van Hoirne map.
See for all the backgrounds of this discovery: 'Schatkaart of kaartschat? Queeste naar de oudste kaart van de Nederlanden' / Marco van Egmond & Elger Heere. – In: Caert-Thresoor 30.4 (2011): 118-126.