Available with Location Referencing license.
Creating the map document
Before publishing a linear referencing service (LRS), you must use ArcGIS Pro to create a map document that contains at least one LRS Network or an event layer.
Learn more about making your data accessible to ArcGIS Server
Publishing a Linear Referencing-capable map service in ArcGIS Pro
After you create and save your map document with symbology using ArcGIS Pro, you can create the map service with linear referencing capability.
Note:
When publishing the resource in ArcGIS Pro, make sure the Linear Referencing check box is checked
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Using the service
A map service with linear referencing capability can be used to build web-based and connected mobile linear referencing apps. In addition, ArcGIS Event Editor consumes your data from this type of map service.
Learn more about authoring a web map for ArcGIS Event Editor