I have just added this to the map of places to fly your drone at Drone Scene:
Land owner permission requirements unknown.
Caerlaverock Castle is on the south coast of Scotland just south of Dumfries. I've put land owner permissions unknown but Historic Environment Scotland do have a known drone policy for their land. However the castle area is surrounded by woods and open fields, permissions for these areas are unknown. The grounds are always open, there are no gates etc. you can drive in anytime. I flew between 7pm - 8pm in the evening when there was hardly any one there.
The originator declared that this location was not inside a Flight Restriction Zone at the time of being flown on 26/08/2021. It remains the responsibility of any pilot to check for any changes before flying at the same location.