Denver’s UV index runs 20% above sea-level cities at the same latitude — the altitude strips out that much more atmosphere. LoDo’s five-story warehouse stock is the counterweight: Wynkoop, Wazee, and Blake streets sit in building shadow through the afternoon, and Union Station’s great hall is the air-conditioned join between them.
These picks use the warehouse grid and the Cherry Creek path’s below-grade cool. Skip the 16th Street Mall at midday — the transit spine is shadeless where the towers step back.