HERE Map Content - Schema
HERE Map Content Developer's Guide

# Special Explication

## Definition

Special Explication indicates a point where a road splits into two or more roads. If no route guidance advice was provided, the driver may not be able to determine in which direction to continue.

## Usage

The Special Explication relationship can be used for map display and route guidance.

## Specification

At qualifying decision points (see rules below), two or more Special Explication conditions are always added, one for each road segment after the split. The following image shows a case where Special Explication is required.

• The Access Characteristics of the Special Explication condition is flagged for all Vehicle Types.

• A Special Explication condition is applied when:
• The driver perceives a non-Controlled Access road as splitting and instruction to keep to the left or right is necessary to continue in the correct direction.
• The driver perceives a controlled access road as splitting into two or more controlled access roads.
• The driver perceives a Highway-to-Highway Connector as splitting into two or more Highway-to-Highway Connectors.
• The controlled access road widens to include two (or more) extra lanes for at least 1000 metres before the decision point. In this case, the driver perceives a motorway as splitting into a motorway and a Highway-to-Highway Connector.
• A Special Explication condition is not applied in situations where an instruction to keep to the left or right is not necessary. The following are examples:

• Splits of low speed ramps
• Highway splits on approaches to toll structures to accommodate different toll paying options
• Motorway with exit ramp