Drive out the far side of Hopeman and take the second right, heading toward Duffus, then keep following that road until you see a sign for a road on the left, for Duffus Castle. After a few minutes on that road you should see another sign for the castle. Go down the farm track type road and visit the wonderful ruins of Duffus Castle.
Find out more:
Duffus Castle: https://www.historicenvironment.scot/visit-a-place/places/duffus-castle/