In the page's words:

On April 6 and 7, 2024, we invite you to take a closer look at Cologne's tourist attractions free of charge on "Discover Cologne Day". For the fifth time, locals and guests can get to know a different side of Cologne and learn new things about (their own) city.
Among the more than 30 free guided tours and many other experiences, you can, for example, cycle through Cologne's art jungle, explore the iconic stalls on a tour through the Südstadt district or visit exhibitions at the artothek and Museum Ludwig.
All you have to do is book your place in good time at www.koelntourismus.de/entdecke-koeln.

06. und 07. April 2024