Bierum was protected from flood by building it on an artificial mound, a so called terp or wierde. The church was traditional build on the highest point of the terp. The region of north east Groningen where this historical village is situated is frequently hit by earthquakes caused by gas extraction of the largest natural gas field in Europe, the Groningen gas field.© 30 aug 2016 Marco van Middelkoop/Aerophoto-Schiphol