The Meuse-Argonne ceremonies take place at the ABMC’s Meuse-Argonne American Cemetery on Sunday, September 23rd. Specific information can be found here.
From that page:
September 23, 2018, at (All day)
Come to Meuse-Argonne American Cemetery on September 23, 2018 at 6:30 p.m. to participate in a luminary event that will help mark the 100th anniversary of the World War I Meuse-Argonne Offensive. As dusk falls at the cemetery, thousands of headstones will be lit with candles, creating a powerful image of light overpowering the darkness. Attendance is free and open to the public.