(CHICAGO) CTA Brown Line riders will need to plan for extra travel time this weekend as track work reroutes elevated Loop trains onto the Red Line subway tracks.

Ongoing work on the Ravenswood Connector – the two-mile section of elevated track between Armitage and the Merchandise Mart – will require Brown Line trains to be rerouted underground starting at 8 p.m. Friday, according to the CTA. The reroute will last until 4 a.m. Monday.

During this time, all Brown Line trains south of Fullerton will operate on the underground Red Line tracks making all stops between North/Clybourn and Roosevelt in both directions, the CTA said. Brown Line trains will operate like normal between Kimball and Fullerton.

Riders that normally need to board or exit from the Armitage, Sedgwick, Chicago and Merchandise Mart stations will be able to take free shuttle buses in both directions between Fullerton and Clark/Lake, the CTA said.

A shuttle train will also operate around the Loop to connect Brown Line service in the subway with shuttle buses at Clark/Lake, according to the CTA. Riders can board this train from the platforms normally served by the Brown Line at all elevated Loop stations.

The track construction work will require 10 additional temporary, weekend-only reroutes of Brown Line trains to subway tracks, which are scheduled through the fall of 2015. The next reroute is tentatively scheduled from May 8-11