Happened to stumble onto the historic battlefield somewhat by accident. We were looking for a local breakfast venue when we discovered the Battlefield Cafe, aptly named being it is right at the base of the battlefield! Aside from the delicious waffles at the cafe, the battlefield itself has a little museum located at the base of the hill that I highly recommend going into first (voice of experience speaking) that way when you go out onto the field, you will have a better perspective of the historical happenings.
As most battlefields of the time, the two enemies were often buried within the same grounds due to speed of decay especially during the summer months. Over time, these headstones appear to be sinking into the ground but rather it is the embankments are growing taller as the organic matter builds up. According to laws of the National Park Reserves, these headstones can not be raised being that would be defacing their historical value. I would give it 20 years and the rules will bend a little and lead to a different take on preservation.