I'm amazed nobody has said Denver, Colorado yet. The combination of big city plus mountain geography is very unique in the US, but also anywhere in the world I think (I've heard suggestions that Zurich is similar r.e. geography, but the city isn't as big).
If you like being outdoors, this is the place. The culture here is exactly that: to be outside all the time skiing, cycling, climbing, hiking, etc.
Visiting friends there in a week or so... Any suggestions for what to do in winter there that isn't some outdoors sport or something that requires being outside for long periods? Our friends have a young baby so we have a limiting factor in our group.
Also, what is the tech industry like there and what neighborhoods are up and coming but still super safe?
If you like being outdoors, this is the place. The culture here is exactly that: to be outside all the time skiing, cycling, climbing, hiking, etc.
The only downside is that it's quite expensive :(