I grew up in Portland, Oregon. It is hard to say whether it is over 1 million now or not, as that would depend on how far into the suburbs you want to extend the "city". Within the actual city limits it is around 500,000.

The big key for me becoming a backpacker was that my parents were teachers and we always took camping trips in the summer. When we camped, we always hiked. It was the cheapest way to get out of town. I loved camping and hiking from almost as soon as I could walk and talk.

The next biggest key was living in Oregon as a teenager when the first surge of the big backpacking wave broke in about 1970. I became an REI member with a number just over 170,000. At the time it seemed to me like I was jumping the bandwagon pretty late, with more than 150,000 people ahead of me.