Hard to pick just one. I've been to 50+ countries, and there's something interesting in all of them. But here are my choices.
Despite its numerous problems, I still love California, especially the Eastern Sierras and yes, SoCal. It's diverse, people don't always get along, but it's complicated, crazy, and wonderful. Not too many places where I can drive from the ritzy beach to the grit of Compton in 20 minutes, and eat a different cuisine for each meal for a week.
Oregon, because that's where I grew up. On a very clear day, you can see 5 volcanoes from Portland. And the volcanic stuff near Bend, McKenzie Pass, Sisters, LaPine, is one of a kind. Lots of hidden treasures and an incredible diversity of landscapes.
And Northern New Mexico / CO, because I've been spending a lot of time there recently, and there's something about the landscape, the light, and its mix of cultures. Seeing the area after a winter storm starts to clear is breathtaking.
For Canada, I'd choose BC. Vancouver is one of the world's great cities, the food and nature rock. And just by looking at the mountains north of the city, you realize that it's the beginning of a wilderness that stretches for hundreds of miles.
And hell, I'll toss in Europe. My pick would be Austria for the Alps, the nice mix of the high culture and mountains. I like Innsbruck, for having the mountains literally within walking distance, the historic old town, and having hot, outdoorsy guys

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