The <a href="https://en.wikipedia.org/wiki/Post_Tower" class="extiw" title="en:Post Tower">Post Tower</a> in Bonn at night with yellow-and-red Christmas illumination. This illumination changes its colours into all possible combinations of red, yellow and blue.
<ul><li><a href="//commons.wikimedia.org/wiki/File:Post_Tower_X-Mas_yellow-red.jpg" title="File:Post Tower X-Mas yellow-red.jpg">Post_Tower_X-Mas_yellow-red.jpg</a>: <a href="//commons.wikimedia.org/wiki/User:H005" title="User:H005">H005</a></li>
<li>derivative work: <font style="font-family:Georgia"><a href="//commons.wikimedia.org/wiki/User:Jovianeye" title="User:Jovianeye">Jovian Eye</a> <sub><a href="//commons.wikimedia.org/wiki/User_talk:Jovianeye" title="User talk:Jovianeye">talk</a></sub></font></li></ul>
CC BY-SA 3.0
<ul><li><a href="//commons.wikimedia.org/wiki/File:Post_Tower_X-Mas_yellow-red.jpg" title="File:Post Tower X-Mas yellow-red.jpg">Post_Tower_X-Mas_yellow-red.jpg</a></li></ul>