Light the candles and ice the cake: Colorado’s best-traveled expanses celebrate their 25th birthday this year. Since 1989, the Colorado Scenic and Historic Byways program—started by former Governor Roy Romer to make the state’s roadways more than just, well, roads—has turned Centennial State travel into an experience. Each of the 25 picturesque routes provides recreational and educational opportunities based on a theme, such as history (try the Gold Belt Tour in southern Colorado), archaeology (the Dinosaur Diamond, which stretches through Grand Junction and Fruita), and geology (the Highway of Legends in Trinidad). Spanning more than 2,490 miles, these lanes attract millions of tourists from around the United States each year. As summer unfolds and you’re itching for a road trip—whether it be by car or bike—look for the blue and white columbine road signs that promise inimitable adventure ahead.