I live in NYC. I can tell what stores and neighborhoods I am walking by just by the smell.
Tangerines? I must be going by a Jamba Juice.
Bread? There must be a bakery somewhere.
Urine? This must be a popular street to walk your dog.
Fish? I must be in Chinatown.
I used to live near to the Vimto factory. On good days the air smelled of …Vimto.
Vimto BTW is a British soft drink made from blackberries and othere FOTF
I live near a sewage-treatment plant and a commercial bakery. Sometimes, when I leave the apartment, I smell chocolate-chip cookies. Sometimes, I… don’t.
My parents’ house is just on the other side of the freeway from a McDonald’s, KFC, Applebees and Chili’s. The smells that waft over to their yard the most are McDonald’s and KFC.
We rarely eat fried chicken, but eat it more than we normally would since their yard often smells like it and reminds us how delicious KFC can be.
I used to live in Milwaukee and attended Marquette University downtown. You either smelled Miller’s next batch of beer or the industrial valley - the Miller was better.
I work in a chemical plant, which is downstreet from a new ethanol plant, and next door to a zinc plant. We get to smell mercaptan (= “natural gas smell”), hydrogen sulfide (= sewer farts), various other sulfur compounds (= more farts), alcohol odors, fermentation odors from the EtOH plant – yeasty or beery, usually – and burnt zinc (… not really describeable). There’s an occasional chlorine smell, or ozony “fresh water” smell, but I like those.
Fortunately I don’t deal with any of the units where the people end up smelling like that. (Prell, by the way, is apparently the only thing that gets sulfurous odors out of your hair.)
I used to travel down to New Orleans to visit a factory that was between a bread factory and a soup factory… with a beignet place on the corner. It was like smelling heaven.
There was an episode of “This American Life” where Ira Glass tries to explain to someone from New York why Chicago is so great. He finally says “…and, the bridges smell like Chocolate.” I’d never been to Chicago, and finally got to go for business a few years ago. I went out for a walk one cold, clear morning, and caught a whiff of chocolate in the air. It really is magical.
There’s often a very nice “horsey” smell in our neighborhood, but I’ve lived here for so long I’m used to it, and I only really notice it after a rain.
For about five years we lived across the street from the River DesPeres in south St. Louis. Originally a natural channel, it was then used for sewer and storm runoff. In the summer, it smelled like - well, an open sewer. The south and southwest summer breezes would blow the most amazing variety of stenches into the front windows of our house.
I lived in the Soulard area of St. Louis for several years, and it was one of those places like others have described where the smell told you the direction of the wind. Yeast was a south wind from the A-B brewery, wind from the southeast brought the smell of a rendering plant and the biting smell from a copper company meant wind from the east.
Nowadays, I live in the country. So it’s fresh air laced with a little horse manure (north) or cow shit (south). The pungency of a skunk is always a nice little bit of spice.
I live east of a papermill. Fortunately I was born here, so my sense of smell burnt out years ago. I can occasionally smell it just before rain.
You can tell visitors to the town. They are the ones holding their noses.
My grandfather was the mill foreman for the deepest zinc mine in the world located in upstate New York. Zinc certainly has a definite odor.
I lived for a time on Hilton Head Island, SC. Most of the time it smelled of salt marsh and ocean but if the wind was right, eau de Dixie Crystals wafted from the sugar plant outside Savannah…sort of like burned spaghetti-os. 
When I was a kid, the local seafood store would deep fry haddock every Friday for the observant RCs. Man, that smell covered the entire South Side.
I work right across from a both a taqueria and a Mexican grocery that makes their own carryout food. I never thought I’d appreciate the smell of beef, onions, chilis, and other assorted spices in the morning so much. Makes me hungry, and I admit I go to the taqueria for lunch far too often.
I used to live down the street from a Korean restaurant. When the wind was right, the whole block smelled like garlic. It was awesome.
As a child in Great Falls Montana, I briefly lived next to the Eddy’s Bakery. Mmmm… bread!
My first job in Pittsburgh (and one I’m returning to next week) was at the Del Monte (formerly Heinz) factory. The Computer Ops building is next to the factory, where they still make baby food, catsup, and gravy.
Usually the place just smells kind of like stale Pork and Beans though. It’s gross.
I used to live a couple blocks from Lawry’s Midwest factory (of seasoned salt fame). Judging by the smell, they only made seasoned salt there. If winds went the other way, we’d smell the Jet-A and avgas drifting over from O’Hare airport.
On rare days, we’d get a whiff of cookies. That only happened on days that Lawry’s was not making seasoned salt. No idea where the cookie factory was, other than “behind” the spice factory.
In San Francisco, a cruel twist of fate placed a Hostess bakery near a gym, so people will come out of the gym and get hit with the seductive aromas of fried and sugar-drenched dough, with an unhealthy dollop of fruity fillings.
I read somewhere that pumpkin pie was the ‘sexiest’ smell. Could be the basis for a movie.
I just got the most nostalgic feeling for NYC now. Must be time to go down.
I have neighbors who burn garbage. They are doing some remodeling and regularly burn scrap wood, old insulation, drywall, old furniture, plastic, household garbage. They then sit around in crappy lawn chairs to enjoy their “campfire”. Our joke is that if their septic ever floods, they will treat it as an ornamental pond.
Meanwhile, in my backyard I go out of my way to burn fragrant wood; sassafras, oak, etc.
I’m just happy that you cannot view their backyard from my backyard, even if the smoke finds its way. 
Sometimes when driving up I-95 I want to take the drive straight through Richmond instead of the 295 bypass (which is slightly longer length wise but a bit faster time-wise,) just so I can go past the cigarette factory. Which smells awesome, and I don’t smoke or even like cigarette smoke smell.
What you smell is the nutrients & taste being baked out of it.
My one time in NYC, when I smelled urine it was going down the stairs for a subway. Dogs had no input. 
Orange processing plant. Ew. Smells of burnt oranges at some times of the year.