Pacific North West
We have friends in Portland, OR and friends and family in Seattle, WA and I have traveled from San Luis Obispo, CA to Vancouver, BC (not on the same trip) by train and I have visited Bellingham, WA a number of times and taken numerous WA ferries. Lots of mountains, rivers, sea, islands, trees. A little more spread out than the UK, with less micro-environments in places, but pretty good.
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