A smell that takes me straight back to my childhood is creosote. We had a cabin on a remote shore of a (at one time) remote lake and we had to park next to the railroad tracks that ran between our property and the dirt road. Some of the neighbors put in railroad crossings, but we didn't. We simply had a wide grass and gravel parking spot. Walking across those tracks was the sure smell that we were at this favorite spot. Also, we were beachcombers, we fished a lot, and took ferries on Puget Sound, and any time you were near a dock or pier you smelled the creosote on the pilings. Finally, I also spent a lot of years climbing mountains and working for the Forest Service. Those dirt and gravel roads were oiled every so often to keep the dust down, and again, it was creosote or something that smelled so much alike as to bring the same reaction. So now, down here in Texas, when I come across creosote, it transports me home to Washington!