Cities smell.
In Vientiane, it was primarily woodsmoke. Wood is still the most common fuel, so the city always had at least an undercurrent of smokiness about it, though at mealtimes on particularly still days, it became so thick and heavy that it must be an asthmatic's nightmare. A nice smell, though. Probably terrible for your lungs but kinda homey.
Flying out of Laung Prabang, where the air is fresh and damp, except for the odd drift of incense coming from one of the many temples, we flew straight into Bangkok. I had only actually visited once before but the minute we got out of the cab it all came rushing back - mostly via my nostrils. Its a funny smell, Bangkok: complex and polyvalent as befits the massive, sprawling metropolis that is it. Its kind of sweet and kind of dirty. I would guess at a recipe that is 2 part sweet chilli sauce, 2 part fish sauce, 1 part lemon grass, mixed in with 1 cup of sump oil, a smattering of mildew, a burst of neon and seasoned with an occasional sprinkling of open drain and lightening. Not unpleasant, but not exactly something that you would dab behind your ears.
Just as homey as the aromatic woodiness of Vientiane is Edinburgh's distinctive but sporadic pong. One of the things I really love about Edinburgh is the smell that comes over the city - and I mean the whole city, including inside your own house if the window's open - when the brewery is brewing and the wind is from the west. Its a kind of yeasty baking smell, which always reminds me of the very fine beef burgundy pies that I used buy at the Schwobs in King Street decades ago as an indulgent winter treat. Its a kind of wholesome, warm smell which gives you an appetite. Makes your stomach rumble if you are hungry, though.
I am not sure the same applies to one's home town. I think you are blind to it, like you are blind to the distinctive aroma of your house. There are a few that stick in my mind though. One is the salty assault of a southerly change as it sweeps up the bay. The other is the smell of wheat or grass tinder dry and baking in the heat.
The third was responsible for one of the worst pangs of homesickness I have had since I left. I was out for a post-dinner stroll in the old part of Boulder City. This part of town is the deco era creation which sprang up as they were first building Hoover dam. Walking through the quiet streets with its palm tree-ed parks and deco houses in the dark, I guess I had already been subconciously lulled back into an Elwood frame of mind. Suddenly there was a huge, suffocating billow of jasmine blossom. How many evenings had I got off the train or tram, or stumbled home from parties and pubs and bands and friend's houses, or driven through a summer evening with an elbow hanging out the window of my faithful car, and known that once I started smelling jasmine I was home. Being hit with it there in Nevada seemed like some cruel hallucination intended to trick me into getting lost. I think I burst into tears.
An America Legion bowling hall appeared just in time to remind me that home was still safely where it belonged, down there at the bottom end of the southern hemisphere.