Though we can’t all indulge in every national food holiday, it’s easy to get behind National Coffee Day. Sept. 29 kicks off the caffeinated day, and Denver has plenty of places you can go for your caffeine fix. Here are spots throughout the city you can go to celebrate the holiday. Caribou Coffee Rather than handing out free coffee to customers, Caribou Coffee — which boasts 21 locations in Colorado — is taking a charitable approach to National Coffee Day.