It's an interesting topic, scent is the strongest sense when considering memory recall.
Certain perfumes remind me of different times in my life, many I don't even know the names but they take me back to when I was first dating my wife, or the smell of my grandmother's perfume that she always wears reminds me of her. When my other grandmother passed, we were going through all the things in her house and i found an old bottle of hair tonic, I opened it and I swear it was like my grandfather who passed many years prior was standing right there with us. I never even knew that was what his "scent" was derived from and never even really bothered to care until that moment. I kept the bottle and still have it to this day, just for memories.
And then there's the smell of airbag accelerant, which immediately takes me back to a bad car accident I was in. I get uneasy any time I smell that, which thankfully isn't often, only once since the accident and that has been 15 years ago.