Google Calendar is below. For reasons still to be explained, users are seeing error messages, making it clear that the site is not fully functioning.
By consulting the Google products status website, we are given information that this is a Calendar only problem. This one has problems since 15:22 pm today.
Update : Google Calendar returned to normal by 6pm
In our test, we were able to fully access the application, but the site is down. One of the error messages that appears directs users to the service status page.
At the moment, the most affected European countries according to the site DownDetector, are France and the United Kingdom. Although Portugal has little prominence in the map achieved, in our tests proved to be practically impossible to access the service through the site.
This is a problem that is only affecting the Calendar. That is, no other Google service has been hit by these issues.