The first Pikes Peak Hill Climb was promoted by Spencer Penrose, who had developed the narrow carriage road into the Pikes Peak Highway. The inaugural Penrose Trophy was awarded in 1916 to Rea Lentz with a time of 20 minutes 55.60 seconds; in the same year Floyd Clymer won the motorcycle class. A popular stock car class was added in 1929.
Through the post-war decades, Louis Unser and rival Al Rogers traded victories. During this period the event was part of the AAA and USAC IndyCar championship. In 1953 the Sports Car Club of America began sponsoring the event, and course records fell every year from 1953 to 1962, the longest such streak in the event's history, with many set by Bobby Unser.
A new era began in 1984 when the first European racers took part. Norwegian rallycross driver Martin Schanche arrived in a Ford Escort Mk3 4x4, and French rally driver Michele Mouton competed in an Audi Sport quattro. Mouton, with co-driver Fabrizia Pons, won the Open Rally category and returned in 1985 to take the overall victory and course record with a time of 11 minutes 25.39 seconds.
In 1987, Walter Rohrl won the overall race in an Audi Sport quattro S1 with a record of 10 minutes 47.85 seconds. In 1989, Finnish former World Rally Champion Ari Vatanen won in a record time of 10 minutes 47 seconds in a turbocharged Peugeot 405 Turbo 16, an effort captured in the award-winning short film Climb Dance directed by Jean-Louis Mourey and released that year.
The City of Colorado Springs began paving the highway in 2002 following a legal challenge by the Sierra Club over erosion damage. Approximately ten percent of the route was paved each year. During this transitional period, Japanese driver Nobuhiro Tajima dominated in Suzuki machinery, scoring six overall victories from 2006 to 2011 and setting two course records. His 2011 record was the first to break the ten-minute barrier.
The 2011 event was the last to include any unpaved sections. The fully paved 2012 race saw a greatly expanded field. Rhys Millen set a new overall record in the Time Attack division. Sebastien Loeb shattered the nine-minute barrier in 2013, completing the course in the Peugeot 208 T16 Pikes Peak with a time of 8 minutes 13.878 seconds, while Rhys Millen finished second with 9 minutes 2.192 seconds, himself beating his own record by more than 44 seconds.
Electric vehicles competed sporadically at Pikes Peak from the early 1980s. Their presence grew steadily through the 2010s. In 2015 Rhys Millen took overall victory in an electric car. In 2018, Frenchman Romain Dumas drove the all-electric Volkswagen I.D. R to an overall record of 7 minutes 57.148 seconds, breaking the eight-minute barrier for the first time and surpassing Loeb's existing record by more than 15 seconds. The 2018 result marked the first time an electric car had set the outright course record.
Motorcycle competition has been part of the event since its inception in 1916. Floyd Clymer won the inaugural motorcycle class on a British Excelsior. Motorcycle racing was intermittent through the early decades, becoming an established part of the programme from 1991 when a new staggered-wave start system dramatically improved safety.
The motorcycle programme ended abruptly in 2019 after four-time event winner Carlin Dunne was killed less than a quarter of a mile from the summit finish line while riding a prototype Ducati Streetfighter V4. Following a review after the 2021 running, motorcycle competition was permanently discontinued. The fastest motorcycle time ever recorded at Pikes Peak was set by Rennie Scaysbrook on an Aprilia Tuono V4 with a time of 9 minutes 44.963 seconds during that final 2019 event.
The event's structure has always accommodated diverse machinery. Current divisions include Unlimited, in which any vehicle meeting safety requirements may compete and from which the overall winner typically emerges; Time Attack 1 for production-based vehicles; the Porsche Pikes Peak Trophy by Yokohama for Cayman GT4 Clubsport variants; Open Wheel for traditional single-seaters; Pikes Peak Open for modified production vehicles; and an Exhibition Class for vehicles that do not fit other categories but are eligible to attempt the overall course record.
The Pikes Peak International Hill Climb is unique among major motorsport events in its scale, altitude, and the variety of machinery it attracts. The transformation from a dirt and gravel course to a fully paved highway fundamentally altered the nature of competition, enabling the string of record-breaking performances that have defined the modern event. Its role as a proving ground for emerging powertrains, from turbocharged rally cars in the 1980s through the electric revolution of the 2010s, has given Pikes Peak an influence on automotive technology that extends well beyond motorsport. Running uninterrupted since 1916 with very few exceptions, it stands as one of the defining tests of driver and machine in all of motorsport.