Back in 2016 I visited the Pikes Peak Highway for the first time since it had been completely paved. The Pikes Peak Highway was completed in 1915 and ascends a little over 19 miles from US 24 generally southward up to the 14,115 foot summit of Pikes Peak. The Pikes Peak Highway is mostly known for the Pikes Peak International Hillclimb which began in 1916. Between 1939 and 1947 the Pikes Peak Highway was part of Colorado State Route 250.
https://www.gribblenation.org/2020/04/2016-summer-mountain-trip-part-26-pikes.html