It is currently possible to add a Garmin Connect Calendar to a Google Calendar by adding it via its URL. However, there are two problems:
1) The calendars do not seem to be immediately synced: if you add something from within the Garmin Connect Calendar application, it is not immediately reflected in for example Google Calendar. It probably takes a day or so to sync. 2) Only the next 30 days are visible in Google Calendar. See also https://support.garmin.com/faqSearch/en-US/faq/content/UVAoDoRAgl1d75WQc4aGEA that seems to explain this.
The above two things are quite annoying for people who would like to see their Garmin Connect Calendar next to their other calendars for day-to-day planning.
I'm not sure whether this is a problem on the Garmin side or on the Google side, but I think 2) is the most important issue to solve.
Would be helpful for me. I work shifts and get my working calendar (how do you call that?) two months in advance. This way I could consolidate my workout with my shifts better. But I grant that this scenario is only apllicable for a small group of people.
Would this maybe be why, when I just tried to add my Garmin Calendar to my Google Calendar only three days of the training plan showed up? Do I have to wait until tomorrow to see the rest of the training plan on the calendar? The training plan starts on December 17 and only three days showed up. That's because it's only 3 days after November 17? That's silly.
Day-to-day planning was maybe not the correct wording from my side. What I mean is the following: I enter all the races I plan during a year in my *Garmin* Calendar. In my *Google* Calendar, I plan for example when I have holiday from work, or when my kid is with me or not (I'm co-parenting), so I know on what day I can race.
Being able to see the full Garmin Calendar in Google Calendar would for example allow me to plan for the summer-races already in January. Now I always have to open up both Google Calendar and Garmin Connect Calendar to see both full calendars and be able to do this kind of planning.