Smells/senses you associate with certain highways/areas

[roadman65]

Paper Mill odor emitted from the Georgia Pacific Plant in Brunswick, GA when traveling I-95 between US 82 and US 25/341.

[TheHighwayMan3561]

Microwave popcorn - MN 100 between 70th St and I-494
Paper mills - I-35 in Duluth and I-535

[Rothman]

Microwave popcorn - MN 100 between 70th St and I-494
Paper mills - I-35 in Duluth and I-535

Huh.  Never smelled anything like the Tacoma Aroma in Superior or Duluth.  I do associate a grainy smell to I-535, though.

[Dirt Roads]

I grew up close to the famous "stinky bridge" on I-64 between Scary and Nitro, West Virginia.  The main odor was methyl mercaptan from the Fike Chemical Plant, which was abandoned in 1988.  The smell stayed around for years afterwards.  Mercaptan is the odorant used in natural gas pipelines, and your nose is capable of detecting less than 10 parts per billion.  For the record, locals always referred to this bridge as the "Green Bridge" even during the years that it was painted blue in the 1980s and 1990s.

[Dirt Roads]

Worst:  Back in the late 1980s, I had a handful of railroad crossings on the old B&O North Shore branch in the Troy Hill section of Pittsburgh.  Two of these were adjacent to the old Heinz plant.  The worst smell was when Heinz was running ketchup.  The most pungent smell was when they were running apple cider vinegar, an odor that I actually liked but made some of my co-workers gag. 

Best:  On the north end of the Hart Bridge in downtown Jacksonville when Maxwell House was roasting coffee beans in the morning hours.  Sometimes, the winds would shift from the east and reach the waterfront when I worked at the CSX Transportation headquarters (The Purple Palace).

Most Distracting:  For some reason, we had a lot of signal problems at the west end of the Schenley Tunnel in the Bloomfield section of Pittsburgh.  This location was right behind the old Iron City Brewery.  It certainly didn't smell like beer, but the strong aroma of hot wet wheat, barley and hops was quite distracting at times.

[SSOWorld]

Microwave popcorn - MN 100 between 70th St and I-494
Paper mills - I-35 in Duluth and I-535

Huh.  Never smelled anything like the Tacoma Aroma in Superior or Duluth.  I do associate a grainy smell to I-535, though.

Paper mills all over central and Eastern Wisconsin (Wisconsin River and Fox River).  Try Mosinee - that shit stinks!  close second place is Rhinelander.

Chicago has a unique scent of its own.  (no, it's not shit)

[bing101]

The smell of cow dung on I-5 halfway from Sacramento to Los Angeles that's from Harris Ranch in Fresno County, CA.

[hbelkins]

A ripe outhouse in the middle of July or August = the intersection of Interstates 64, 65, and 71. 

[JayhawkCO]

Paper mill/swamp smell coming into Jacksonville on I-10.

Chris

[sprjus4]

Paper mill on US-58 near Franklin, VA.

[US 89]

There is a distinct smell of cow on any highway in northwestern Texas. US 84 west of Lubbock comes to mind in particular.

[SSOWorld]

A ripe outhouse in the middle of July or August = the intersection of Interstates 64, 65, and 71. 

That university is not quite downtown

[index]

Manure... US 421 south of Wilkesboro, NC.

Repulsive paper mill scent, I-526, specifically the Don Holt Bridge.

A sweet, piney smell, the north end of NC 128. Those fraser firs and red spruces at the tops of some of the mountains in NC make the air smell like a Christmas tree. I love it.

[WillWeaverRVA]

You know you're approaching Kings Dominion on I-95 when you smell the paper mills not far from the highway.

I-95 in South Richmond also has a persistent sewage smell due to both the Port of Richmond and the city's main sewage treatment plant being right off I-95 in that area.

[Rothman]

Oil refineries in NJ near the northern end of the NJTP...and at US 23/I-64 near Ashland, KY.

[CtrlAltDel]

When I was a child, traveling from Chicago to Florida to visit my grandparents, we always stopped for gas somewhere before Indianapolis. I remember that it was something of a shock getting out of the car there, since it was very rural, visually as well as olfactorily, and it was a sign we were well on our way. I couldn't tell you what that smell was though. It was maybe diesel or ethanol, but I don't think so. It didn't seem like manure or anything like that, but it definitely pervaded the air, at least around the gas stations.

[oscar]

The smell of cow dung on I-5 halfway from Sacramento to Los Angeles that's from Harris Ranch in Fresno County, CA.

That huge feedlot is right at the junction of CA 245 with I-5. Always a good time to hit the "recirc" button on your A/C, before you reach that junction.

[frankenroad]

I-75 around the GE Plant north of the Lockland Split smells like gasoline.

I've never really noticed that.  But a few miles south, is a fragrance manufacturer, and there is often a very sickly sweet smell around exits 9 & 10.

[Flint1979]

I-75 on the SW side of Detroit smells like burnt oil and rubber from the Rouge Plant.

[mgk920]

The stench of I-41 by Kaukauna.

That's the kraft process mill that is operated by Thilmany Pulp and Paper in Kaukauna, WI.  The make the brown paper that is used in boxes and bags.

IMHO, worse in the Appleton area is the suburban townships' sewage treatment plant that is along the east side of I-41 just north of US 10/WI 441, between Appleton and Neenah, WI.  The Outagamie County landfill that is along I-41 between Appleton and Little Chute, WI can be pungent, too.

Elsewhere, the steel mills and oil refineries that are along I-90 (Indiana Toll Road) in East Chicago and Gary, IN are definitely memorable.

Mike