Castle Hills are two naturally built mounds near to Upper Boyndlie farm. Leave the A98 at Boyndlie Hall, the farm is a mile down the road. Take the track opposite Upper Boyndlie and continue for 1/4 mile. Here the track widens leaving plenty room for car parking.
The two castle hills are on the left and are called the Eastern and Western. Loads of discoveries have have been found here, see the link, and they have been taken to Aberdeen Museum.
On the western hill can be found the cist, a stone which measures 1.4mx0.6m. From the track to the hills is short but steepish climb. Easy to see why have their names. Today was very warm and sunny, but on a cloudy/misty day I would imagine this place might be quite scary!