As an amateur photographer I'm always interested to see in the half-invisible editorialization that takes place in the way you frame a subject. You have to admit that the whole rest of the city would look dirty if the "2005" photograph was taken on a smoggy day, right? And that would take away from the impact of the river. That's all I'm saying.
Obviously, and the fumes from the cars coupled with the blocking of what breeze there was by the freeway would have made the local situation even worse. A simple matter like the highway stopping the rain from being able to wash away the dust beneath it would have had a great impact also.
I've walked one section before and after ... they did a great job.
BTW, as a photographer, you would love the fact that the bridges are all unique styles, many modern and one even using parts of an original bridge from the 1400's. The pathways below are ever changing, with "rapids", waterfalls and fountains - all lighted at night.
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