City Hall goes Orange in celebration of the SF Giants reaching the playoffs and then going on to play the World Series. This performance by the baseball team led to what is now called Orange Ocotber, where a lot of prominent buildings have gone orange.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/26781812@N00">GPS</a> from San Francisco, USA
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<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/zoxcleb/5128099178/">Evolution Orange</a>