For many years Atrium City Hall organizes the Christmas-Sing-ALong in the Atrium, based on an idea by Herbert Boerendonk. Every year, a Christmas choir is once composed every year which constist of 300 choir members with singers from the region The Hague in the ages of 10 – 90 years.

After rehearsing three times, this Christmas choir will give a concert to over 1.100 visitors. All under the supervision of pianist and conductor Gregor Bak and, for several years, a guest appearance is made by dramatic soprano and TV personality Francis van Broekhuizen.