The MBTA will soon be adding late-night weekend service to subway lines, as well as popular bus routes in the Boston area.

For the first five weekends after the change, commuters can ride for free on any train, ferry, or bus line. The MBTA says most buses and trains will run every 30 minutes during the extended hours. On the Red line, between Alewife and JFK/UMass, trains will run every 15 minutes.

Nine years after pulling the plug on a prior weekend late-night service program, the MBTA this month will begin running all subways and several popular bus routes about an hour longer into the night. It's part of a new fall schedule that also boosts daytime trip frequency across most of the system.