System Wide Radio System Upgrade.
Washington DC Metro (WMATA) 

Installation of the Snake Rack System took place across 100 miles of tunnel in the WMATA system across all tunnel construction types. WMATA crews accomplished the work in less than 3 years, upgrading the Tunnel Emergency 2 way radio, Wifi, Fiber, Power, and Communications cables on one Support system.  Picture attached with the Trilogy Radiating Cables