The race was established by Spencer Penrose, who converted a narrow carriage road into the Pikes Peak Highway. The first Penrose Trophy was awarded in 1916 to Rea Lentz with a time of 20:55.60; Floyd Clymer won the motorcycle class in that same inaugural event. A long rivalry between Glen Schultz and Louis Unser defined much of the interwar period, with the two men winning the event twelve times between them. The stock car class was added in 1929.
After World War II, Louis Unser continued winning into the 1960s in rivalry with Al Rogers. The event was also incorporated into the AAA and USAC IndyCar championship for a period. From 1953, when the Sports Car Club of America sponsored the event, a wave of sports cars arrived and the course record was broken every year from 1953 until 1962 — the longest consecutive run of record-breaking in the event's history — with Louis's nephew Bobby Unser responsible for the majority of those records. In 1971, the event was won for the first time by a non-gasoline vehicle: a propane-powered 1970 Ford Mustang driven by Ak Miller.
European competitors began arriving in 1984, when Norwegian rallycross driver Martin Schanche and French rally driver Michèle Mouton entered with all-wheel-drive cars. Mouton won the Open Rally category that year and returned in 1985 to take the overall victory and set a course record of 11:25.39. In 1987 Walter Röhrl won overall in an Audi Sport quattro S1 with a new record of 10:47.85. The event gained wider international attention through the acclaimed short film Climb Dance, released in 1989 by French director Jean-Louis Mourey, which documented Finnish World Rally Champion Ari Vatanen's record run of 10 minutes and 47 seconds in a turbocharged Peugeot 405 Turbo 16 at the 1988 event.
The Pikes Peak Highway was progressively paved from 2002 onwards following a Sierra Club lawsuit over erosion damage to streams and vegetation downstream from road gravel. The 2011 event was the last to include dirt sections. Japanese driver Nobuhiro Tajima scored six overall victories between 2006 and 2011 with Suzuki cars, including the first sub-10-minute run at the 2011 event.
The 2012 running — the first entirely on asphalt — attracted over 170 entries and saw numerous records fall. In 2013, Sébastien Loeb shattered the nine-minute barrier in a Peugeot 208 T16 Pikes Peak with a time of 8:13.878, while Rhys Millen finished second with 9:02.192. The overall record was pushed further still at the 2018 event, when Romain Dumas drove the all-electric Volkswagen I.D. R to a time of 7:57.148, becoming the first competitor to break the eight-minute barrier and setting the current outright course record.
Electric cars have featured at Pikes Peak intermittently since the early 1980s. Their competitiveness grew steadily through the 2010s: in 2014, electric cars claimed second, third, and fourth overall; in 2015 they swept first and second. Nobuhiro Tajima also broke the ten-minute barrier for electric vehicles in 2013 with a time of 9:46.530. The 2018 outright record by Romain Dumas in the Volkswagen I.D. R marked the first time an electric vehicle had claimed the absolute course record.
Motorcycle competition began at the inaugural 1916 event but was contested only sporadically for much of the event's history, appearing in 1916, 1954–55, 1971–76, and 1980–82 before becoming a permanent fixture from 1991. The gradual paving of the course shifted the winning formula from motocross and flat-track machines toward supermotards and ultimately road-biased sports motorcycles. The fastest motorcycle time at Pikes Peak was 9:44.963, set by Rennie Scaysbrook on an Aprilia Tuono V4 in 2019. Motorcycle competition was discontinued following the 2019 event, after four-time motorcycle winner Carlin Dunne was killed in a crash less than a quarter mile from the finish line while riding a prototype Ducati Streetfighter V4. The decision was reviewed after the 2021 running and motorcycle racing was subsequently discontinued altogether.
The PPIHC currently runs six divisions: Unlimited (open to any vehicle passing safety inspection, historically home to the most exotic purpose-built machines), Time Attack 1 (production-based closed-cockpit vehicles), the Porsche Pikes Peak Trophy by Yokohama (a one-make class for the Porsche Cayman GT4 Clubsport, introduced in 2018), Open Wheel, Pikes Peak Open, and an Exhibition Class for vehicles outside the standard technical specifications.