I’ve seen on the Strava Customer Support site lots of people asking to be able to show off all the challenges that they have completed. As it stands I don’t know which of the challenges you have or have not signed up for but I can quite easily calculate how you would have done if you had. So here it is: a trophy cabinet of all the challenges you have completed and those that you didn’t quite achieve (whether you were trying or not)! Of course this is only currently available for cycle challenges, not running ones.