Paintings from sand, that’s what lacquer profiles of a dike look like. They are imprints from seven centuries of dike construction, made during the excavations by Fort de Schans, just outside of Oudeschild.
Even in the Middle Ages people protected the land from the sea with dikes. The dikes from those days were made from other materials than nowadays. On the lacquer profile, you see that the oldest part of the dike, which dates back to the 14th century, was made from eelgrass. Eelgrass was referred to as seaweed (in Dutch ‘wier’), which is why such a dike was called a ‘wier’ dike. Eelgrass grew in extensive fields in shallows in the Wadden Sea. It was harvested, dried and tamped down between rows of poles.
The arrival of the shipworm made an end to ‘wier’ dikes. The poles, which were needed to keep the eelgrass in place, were affected. That’s why people started using sand and stones for building dikes. The lacquer profile is made up of separate imprints, which together display a cross-section of the dike. Various layers in the ground are easy to identify in the imprints, which were made with a special kind of lacquer.