Moscow, Russia. It's both cool and cold here ;)
Portland. A million different cultures in one place. It's phenomenal.
I would have to say it was the 2 years I lived in Germany. It rarely got above 80°F and with windchill factor, it got as cool as -20°F in the winter. Other than that, I lived in Colorado for 3 years. It gets pretty cool there too but Germany was cooler.<br />
...btw, they were both a blast to live in. Had some of the best times of my life and met the best people.
Minnesota. It was very cold there. I don't know why.