Nicosia's motorised segmented street network - manually edited

A dataset containing spatial and attribute data for motorized segmented street network.

The extents of the datasets refer to the Urban morphological zone of Nicosia, and a buffer of 20 km around it. The motorised networks exclude all streets that are pedestrian-only and where cars are excluded. The network layers are based on OSM  (openstreetmap.org, http://download.geofabrik.de , date of download 01-11-2023). The original road-centre-line maps of the cities were edited based on the same basic representational principles and were converted into line-segment maps, using the following software: Space Syntax Toolkit (SST) version 0.3.10 for QGIS (version used LTR 3.28), Place Syntax Tool version 3.2.5. 

The coordinate system is CGRS93

In the final line-segment maps (GIS-layers) all roads are represented with one line irrespective of the number of lanes, except for Motorways and Truck, which are represented with two lines, one for each direction, again irrespective of the number of lanes.  The same editing and generalising procedure, aiming to remove errors, was followed. This process included removing duplicate and isolated lines, snapping and generalising with the aid of the SST: RoadNetworkCleaner tool.

The snapping threshold used Xm (end points closer than Xm were snapped together). The generalising threshold used was Xm (successive line segments with angular deviation less than Xm were merged into one). Where X is the standard threshold used in the SS toolkit measures. In the final editing step, all road polylines were segmented to their constituent line segments. The aim was to create appropriate line-segment maps to be analysed using Angular Segment Analysis, a network centrality analysis method introduced in Space Syntax.

All network layers are complemented with an “Unlink points” layer, a GIS point layer with the locations of all non-level intersections, such as overpasses and underpasses, bridges, and tunnels. The Unlink point layer is necessary to conduct network analysis that takes into account the non-planarity of the street network.