The source data exists in order to provide linear geometries against which official railway names can be recorded and to provide contextual data for Landonline users.
A railway centreline in this layer will typically consist of a centreline wholly contained with a parcel(s) with an intent of "railway"
The railway centrelines do not represent actual railway formation but the presence, and general location of a gazetted railway for contextual uses.
Railway corridors on the record sheets were usually sufficient to provide an indication of where a railway existing was in relation to meshblock and electoral boundaries. These were transferred to Landonline at inception.
Railway centrelines were originally created independently of the cadastral and electoral processes for the Digital Cadastral Database (DCDB). The Railway names that were stored were those as approved by Tranzrail, the NZ Geographic Board. Where the Railway name is hyphenated, it is entered without spaces separating the parts of the name and the hyphen. Unnamed rail segment features had the Railway Name populated as RAILWAY.
Software routines were used to generate lines along the centre of the legal rail corridors and then railway attributes were attached. The centrelines were created to enable the automated printing of railway names along the centre of the railway corridors on any map that contained part or all of the corridor. Late in the Landonline design it was recognised that it would also be desirable to add railway centrelines. The solution implemented was to add them to the road centreline table, changing the original purpose of this table from 'road centrelines' to 'carriageways'. It was not however practical to rename the table at that point. For the LINZ data service Road and Rail centrelines have been separated, with this data layer containing only 'rail'