Murdostoun  Murdostoun is an estate in North Lanarkshire, Scotland, which includes a castle, (Ordnance Survey Grid Reference NS8257), which lies on the South Calder Water near the village of Bonkle in the parish of Shotts, North Lanarkshire, Scotland. The name Murdostoun was derived from the words Murthock and Toun which meant dwelling of Murthock. Murdostoun can refer to the ancient barony of the Scott and then the clan, the castle built by the Scotts or a bridge over the South Calder Water. The Murdostoun Estate contained many farms. The main ones were: Foulburn, Castlehill, Easthouse, Westhouse, Penty, Muimailing, Easterhill, Westerhill and Shapenknowe. Other near the Murdostoun Castle were Eastwood, Westwood, Rosebank and Heughbank. The estate was reported to consist of 1,760 acres in 1872. The former Allanton Estate lay just to the east. Murdostoun Castle lies 1100 meters west-northwest of the village of Bonkle. Murdostoun Castle was built by the Scott family in the 15th Century and was constructed as a keep or fortified residence. It stands on a good position high above the South Calder Water and was one of many built as a defensive measure across the Forth and Clyde Valley. The typical design of these houses was of a tall square block of three storeys, set within a courtyard, with thick walls and battlements. For security, no access from the ground floor to the two floors above, could be made. The main hall on the first floor was reached by a removable staircase from the Courtyard and access to the top floor, where the sleeping quarters were located, was by a narrow stair within the walls. Other rooms were also created within the walls. The roofs were made of stone for protection against fire attacks and parapets and fighting platforms were provided around the wall tops. Murdostoun Bridge, dated to 1817, is a single-span segmental-arch bridge constructed predominantly of yellow ashlar sandstone, with chamfered wing wall, hoodmoulded arch ring and low ashlar parapets. Murdostoun Bridge crosses the South Calder Water which divided the Murdostoun Estate from the Allanton estate. The river is also the parish boundary. Equidistant between the Allanton estate village of Bonkle and Murdostoun Castle. The bridge was probably built by the Stewarts of Allanton, stylistically it is similar to the triple span Allanton House bridge.