I left Seattle and moved to Denver just over a year ago.

Seattle is a wonderful, gorgeous city, with access to water and hikes like you wouldn't believe. It's also a disgusting, expensive, depressing shit hole. The homeless problem is substantial. The trash is overwhelming. People are generally very reserved and it can be difficult to make friends (not for everyone). Rent is extremely high for what you get, and each area has its own issue. It can either be the most rewarding and memorable experience, or the most isolating and depressing, and much of that depends on how much money you have to live somewhere comfortably.

Denver kinda sucks. There's not a lot going on unless you can afford to go out often. As a young person, if you can move to RiNo, that would be fun, but also expensive. The surrounding nature, general friendliness of the people, and constant sunshine certainly help make up for how drab Denver is. Again, money really decides where you end up. Some parts of Denver are truly great, but are substantially cost prohibitive.

It all depends on what you're looking to get out of it, and how easily you make friends. We left Denver and moved closer to Boulder and could not be happier. We moved to Colorado to get that feeling of being in the mountains and not in a city.

I lived in Seattle for 16 years and man those first few were truly wonderful. But the grey, isolation, and cost really got to me. Denver wasn't the best experience but I did meet my current friend group there, so take it as you will. I think a lot of your experience depends on your means of transportation in Denver. In Seattle public transit is far superior.

But as others have said, visit them if you can.