If you're visiting Rochester, then it's worthwhile taking a short walk across the River Medway bridge to Temple Manor in Strood, the remains of a large estate that was given to the Knights Templar in 1159 by Henry II. The stone Manor building you can see today was erected around 1240.
Temple Manor in Strood, former home to Knights Templar
The Knights Templar were a large military order formed during the Crusades to protect travellers to the Holy Land. They were a powerful rich group who had many properties including the fascinating Temple area in London which you can see on this walk.
The Knights Templar retained possession of the Strood estates until the early 1300's, and control eventually passed back to King Edward II. Over the years many modification were made to the Manor building, but by the second World War it was derelict.