I don’t know what it is about the air in Peru, but things get pretty grimy when they’ve been hanging out for a while. I don’t know if it’s pollution, or just the fact that Lima is more or less in a desert. You don’t think of Lima as a desert because there are so many green areas, but you forget that those green areas only stay green because trucks drive by in the middle of the night to spray water on them. Anytime the wind kicks up it pulls sand off the nearby mounts and drives a wall of dust through the city. The poor Peruvian flag in the above picture took the worst of it, as did this road sign:
Actually I’m more inclined to believe that the road sign has been stained by exhaust as it’s more black than gray…and it’s hanging right over a highway. Still, in a few more years you won’t be able to read it at all.