The topography.

Secret routes that beat rush hour traffic.

The two weeks in October with clear skies and no humidity that the city looks its best.

Low cost of living.

Food scene that bats way above population size.

Absolutely absurd interactions with strangers. Chronic oversharing. Extreme and weird generosity and crankiness. Personalities and stories that seem fictional but aren't. There's some magical realism in the blood of this place.

Cons: I have heard from many transplants that the town feels insular and they have a hard time breaking in socially. I am friends with more than a few transplants and I feel like as long as you make friends normally at work and/or do an activity (climbing, etc.) and/or get involved in something (a church, the elks, whatever) it's not a problem. That said, I have heard it.