The remains of the Abbey can be visited
Harsefeld Abbey

The monastery ruin of Harsefeld in Lower Saxony, near Stade, bears witness to a once significant Benedictine abbey. Originally founded as a collegiate church for secular clerics, the complex developed into an influential monastery whose history was marked by theological and secular conflicts.
History+
The origins of Harsefeld Monastery date back to around 1002, when a collegiate church for secular priests was established. This foundation, under the patronage of the Mother of God Mary and the Apostle Bartholomew, served to atone for a political murder in which the Counts of Stade were involved. Around 1100, it was transformed into a Benedictine monastery. The first monks came from Ilsenburg, bringing their monastic rules with them. Pope Paschal II placed the monastery directly under papal authority, granting it extensive freedoms.
Image: http://www.wehrbauten.de/thread.php?threadid=609
Location: 53.4539, 9.5019