Smeaton Castle is a much-changed structure, and is now known as Dalkeith Home Farm. In 1450 the lands of Smeaton belonged to Dunfermline Abbey in 1450, and it is from this time that the castle dates. It was once a large and impressive structure, with circular towers at the four corners of an oblong courtyard. Only the north-west and south-west towers still remain – the former to a reduced height, the latter to four storeys, although the floor levels have changed. Attached to the south-west tower is a smaller square tower.
Connecting the two towers is a section of original curtain wall (forming the west side of the property), although it has been altered with the addition (in antiquity) of windows along its length. The south wall always had the main residence built against it, although the only original external features remaining are two small windows and the basement level.
A moat surrounded the castle, and evidence of it can still be seen on the ground.