Denver and Boulder, in particular, are known for their wide variety of bars, restaurants, concerts, and other nightlife. Most places are still fairly casual, but you may want something a little nicer or trendier if you’re planning a night out. Women could wear a dress, but otherwise jeans, a blouse or button-down, and flats or loafers will be nice enough for all but the most upscale places.
Snow sports: Colorado is a haven for all kinds of winter sports and snow-based activities: skiing, snowboarding, cross-country skiing, snowshoeing, sledding, and more. For most of these and other winter activities, the best clothes are similar. Start with a warm, sweat-wicking base layer and an insulating mid-layer, like a sweatshirt or fleece jacket. Over that, you’ll need a winter coat and snow pants, as well as a hat and gloves. If you’re going downhill skiing or snowboarding, don’t forget your goggles.
Water sports: Water sports in Colorado are nearly as ubiquitous in the summer as snow sports are in the winter. For kayaking, canoeing, stand-up paddle boarding, jet skiing, and so forth, quick-drying clothes made of lightweight fabrics are the most comfortable. Choose things like activewear, tank tops, board shorts, and snug-fitting water sandals, as well as sunglasses and a hat.
Hiking: Hiking is another of the most popular things to do in Colorado, and there are great trails all across the state. If hiking will be part of your trip, make sure your Colorado packing list includes a quick-drying T-shirt or tank top, a pair of hiking pants, and sturdy hiking shoes or boots.
Horseback riding: For many visitors other parts of the U.S. or abroad, going on a horseback ride in the western U.S. is a bucket list activity. Pants for horseback riding need to be fitted and durable but still have some give, so jeans made with some spandex are the best bet. You’ll also need sturdy, close-toed shoes, ideally some type of boots with a small heel.