Ring in the season with the 99th Annual Mayor's Holiday Celebration and Tree Lighting Presented by Reliant, an NRG Company on Friday, November 30, 2018 in the heart of downtown Houston. The spectacular event is a holiday tradition of music, Santa, fireworks and family fun. A towering Holiday Tree, glowing with energy efficient LED lights, shimmering ornaments and a stunning star topper will light up the streets of downtown Houston this holiday season. The event takes place in Hermann Square at City Hall from 6:00 to 8:00 p.m. and is free and open to the public.