Areas in Calderdale which have a 20 mph speed limit. .Tab files (zipped) and .JSON files contain data which can be used in various Geographic information systems. Excel and CSV formats do not contain the 20mph area boundaries but do have the centre point (centroid) of the area. This data has been derived from Ordnance Survey base mapping. (C) Crown copyright [and database rights] (2018) OS (licence 100023069). For more detai...