Discover the old maps of the Netherlands
In previous centuries many maps and town plans were produced of Dutch territory. Focusing on various purposes, generations of cartographers made all kinds of cartographic images of cities, areas, provinces or of the entire territory. Over thousands of these kinds of maps of the Netherlands and the Dutch regions, ranging from small-scale to large-scale, have recently been scanned and made online available. The collection of cartographic documents is also georeferenced, making searching and analysing this collection a lot easier. The maps offer a striking illustration of the spatial development of the Netherlands in the period between 1550-1850.
Since its founding hundreds of years ago, Utrecht University has succeeded in building an impressive map collection. This collection got a great boost when the Geographical Institute was founded in 1908. From that time on, serious efforts were undertaken to set up a systematic map collection. Both the quantity and the quality of the collection developed rapidly. These days almost the entire map collection is housed in the depositories of Utrecht University Library.
It is no surprise that a major part of the collection of old maps is related to Dutch territory. This cartographic material, in origin mostly used for practical matters such as planning and management purposes, was later to turn into teaching and research objects for Dutch geographers and historians in particular. Typically Dutch questions such as hydraulic interventions and land reclamations were often the reason for making the maps.
Body of cartographic sources
Today old maps may be of great importance as historical sources for historical geographers, landscape architects, archeologists, historians and others interested in history. By digitising the old cartographic documents of the Dutch territory a splendid body of this kind of sources has been documented. In addition, the maps have been georeferenced making them easily searchable via a geographical search system. Digitising and georeferencing were done in 2017 and 2018 as part of the project Zet Nederland op de kaart (‘Put the Netherlands on the map’).
Generally speaking, georeferencing means ‘sticking’ a scan of an old map onto a (modern) digital reference map. The scan of the old map is provided with spatial information, making it possible to set up links with the current situation. The georeferencing process consists of matching control points on an old map with locations on a reference map. Provided that enough control points are added, the old map can be reshaped in such a way that the result approaches the geographical reality as closely as possible. In that case, the map can be presented as a layer in modern geographical interfaces and information systems, and is getting more or less a second life.
Georeferencing the scanned old maps was done with the help of the internet application Georeferencer. This application is very suitable for crowdsourcing: a large public putting control points on the map. The project Zet Nederland op de kaart had a kind of ‘multi-stage’ crowdsourcing. First a part of the collection of old maps were georeferenced by a closed group of sponsors, alumni and students. In a following stage the rest of the collection was released for random outsiders. In this way it only took a few weeks to georeference all scans of the old maps.
The innovative software of Georeferencer offers many functionalities. For instance, the georeferenced maps can be viewed in several ways and in different transformations. Next they can be projected on top of each other or next to each other. In addition, Georeferencer gives access to the georeferenced material of other libraries and institutions. An accuracy analysis of the maps is also one of the options offered. An extensive explanation of all functionalities can be found on the website of Special Collections of the University Library Utrecht. In the application of Georeferencer itself you will find many pop-up help screens.
Use in GIS
A large advantage of Georeferencer is that the files resulting from georeferencing can be downloaded directly for the use in GIS systems. For instance, for each map the application offers the URL for ‘Web Map Tile Service’ (WMTS), but also the GeoTIFF is available. If applicable it is also possible to select the reviewed version which has been approved by the library itself, or choose for the latest version which has been adjusted by the user itself or extended with extra control points. Logging in is required if you want to import links or the GeoTIFF: for instance with Facebook, a Google account or Twitter account.
There are several ways to search the collection of georeferenced maps of Dutch areas. Firstly, the library has its own geographic search engine in which can be searched by, for instance, keywords, scale and time period. There is also the website Georeferencer Compare, which not only shows the georeferenced maps of Utrecht University Library but also of many other libraries. Finally we have the website Old Maps Online on which, with some delay, the Utrecht georeferenced map collection will be published.
The collection of maps which was georeferenced in the project Zet Nederland op de kaart contains many cartographic gems. A fine example is a manuscript map of almost three metres long of the river Lek from 1738. Or look at the even bigger forty-sheet wall map of Holland by Jacob Aertsz. Colom, in an early 18th-century edition. And the beautifully coloured four-sheet four-sheet town plan of Rotterdam from 1800 by land surveyor Andries Munro which gives a unique view of the port as it was then and the hustle and bustle directly outside the city walls. Once you get the hang of it, the intuitive application of Georeferencer will invite you to visit many other beautiful and splendid maps!
In the future
As early as 2013 the Utrecht University Library has been engaged in georeferencing parts of its map collection. We now have three related selections of maps provided with georeferences: water management maps, fortification plans and maps of the Netherlands and of Dutch regions. In the future other sub collections will follow.