Route Lists in Webex Calling are lists of numbers reachable through a Route Group. Each Route List is exclusively assigned to a Location that supplies up to 40,000 unassigned numbers from the hosted pool.
Only customers with Dedicated Instance entitlements can see or configure Route Lists in Control Hub.

The figure above illustrates a Webex Calling organization with two Route Lists in their respective locations (SJ & DFW), each of them pointing to the same Route Group/Trunk, which in turn routes to a single Dedicated Instance cluster.

The figure above illustrates a Webex Calling organization with two Route Lists in their respective locations (SJ & DFW), each of them pointing to different Route Group/Trunk configurations, which in turn routes to two different Dedicated Instance clusters within the same customer organization.
For instructions on creating and using Route Lists, see Provisioning Flow to Enable Cloud Connected PSTN for DI.