Signs and murals around Denver declare that “No Coast is the Best Coast,” a proclamation that’s rooted in the Mile High City’s refusal to play the game by any rules other than its own. Here, flannel can be formal; greeting strangers doesn’t make you weird; and when people ask what you do, they mean, How do you spend your time outside? The city is doing much to embrace its rich, diverse history, and yet it’s also moving into the future with innovative restaurants, imagination-defying art, and,...