Click the button to copy the URL into the clipboard.
The calendars are updated once per day so you don't have to synchronize the calendars more often than that.
Badges Calender URL - https://garminbadges.com/calendar/badges
Challenges Calender URL - https://garminbadges.com/calendar/challenges
Note: If you browse to the URL an ics file (iCalender file) will be downloaded. Don't use that in your calendar application since it will not be updated.