Glimpsed from the train by passengers arriving at Edinburgh's Waverley Station is Wellhouse Tower. Its remains are situated in Princes Street Gardens squeezed between the railway tracks and the base of Edinburgh Castle's formidable rock.
Wellhouse Tower was constructed in 1362 to protect and control access to St Margaret's Well. Ensuring water was always accessible to the castle was vital for its occupants. If the castle well ran dry or was blocked – as happened in the siege of 1571-73 – it could not hold out. The tower was therefore of utmost importance though accessing it from the castle was both difficult and dangerous.
Little more than two storeys of Wellhouse Tower survive today. It consists of a main block and wing, the latter enclosing the well. The walls are of locally quarried rubble with an intake at first floor level corresponding to that of the contemporary David's Tower on the castle rock. The tower served as a protection to the well and as a gatehouse to the path ascending the castle rock.
By the 17th century it was in ruin and excavations have uncovered human remains, cannon balls, bombshell fragments and coins dating from Edward I to Oliver Cromwell.
Sadly those visiting Wellhouse Tower today will find it neglected and shabby, covered in vegetation and littered with beer cans and the detritus of modern society