Relative Elevation Nodes (REN)

Coordinate system: 4326 - "WGS 84"


Relative elevation differentiates coincident nodes of varying elevation and outlines relationships between street segments on different planes via node-and-segment connectivity. Relative Elevation Nodes (REN) are a work-around for inherent limitations when navigating through three-dimensional street networks represented on the two-dimensional plane (i.e. computer screen). REN help to establish routing options and are particularly useful where complex overpass/underpass structures exist because they indicate street segments as being on different road-levels; where on the computer screen all streets appear to be connected.

The REN layer, coupled with the Turn Restrictions Table (TRN), generates the most accurate routing. Attributes contained in this file include Relative Elevation, Intersection, Latitude & Longitude.

Note: In 2012, there was a datum change from NAD83 to WGS84.

Additional Documentation