Critchlow Enhanced Roads Network, built on top of the Critchlow Formed Road Network, is a nationwide network specifically optimised for routing applications.
The following notes from the Critchlow Formed Road Network are also applicable here:
A formed road is land that has been set aside and prepared for vehicle traffic. The surface of the road may be sealed, or it may be rough (wheel tracks), but it must be accessible in all weather conditions by a standard, non-SUV, family-type vehicle.
All formed roads that are named (publicly or privately owned, formally or informally named) will be represented within the Critchlow road network.
The Critchlow Road Network follows the following basic principles: 1) It is a connected network. All segments in the dataset will perfectly connect with their neighbouring segments where, in the real world, a vehicle can drive between the road sections represented by the connecting segments. 2) It uses nationally consistent naming standards for all roads, a nationally consistent set of prefixes and suffixes, and nationally consistently applied abbreviations for such prefixes and suffixes. 3) It is composed entirely of lines or polylines. No other type of object is acceptable, including multipolylines. 4) It represents real world road features, such as roundabouts, dual carriageways, ramps and slip roads.
The resource has been validated and quality assured using Critchlow's ISO compliant Monthly Testing Process