At first, I thought, what a cool effect with the bluish purple that reminds me of the 'Royal blue' ink popular centuries ago. There were several sections along this walk that were also illuminated in this manner. Then I remembered that we've been having problems in the city with the street lights turning purple because of some defect in the lightbulbs. So, in all likelihood, this wasn't done by design, but I still think it looks neat, royally so.
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