But the one that he remembers mostly fondly was the 1975 event, as it marked his very first World Rally Championship victory.
Aged 24 at the time, Alen was driving for Fiat in his debut season, with the Group 4 Fiat 124 Spyder at his disposal. His team-mate was fellow Finn Hannu Mikkola, and from the beginning it was a fierce battle between the two of them for victory, as they left Ove Andersson - driving a Toyota Levin - trailing in their dusty wake.
“I don’t remember much about the event itself - it was such a long time ago after all - but I do remember very clearly what my feelings were,” said Alen, 37 years on. “The Fiat wasn’t a fast car, so I was pushing flat-out from the beginning and all the time Hannu was coming too.
“I felt excited and nervous at the same time. Between us, we were both getting away from much more powerful cars. It was a very long rally then, both on gravel and on asphalt, but by the final day I knew I was going to win. I’ve always loved Portugal as a rally because of the beautiful stages and fantastic atmosphere. I don’t think that’s changed at all after all this time.”
Alen himself will be in Portugal next week as a special guest. Following his debut win in 1975, he went on to win the event again in 1977, 1978, 1981 and 1987.