Any calendar in SharePoint can be quickly added to Outlook so that you can access it from your Outlook Calendars view as well as overlay it with other calendars to view them as one calendar.
Open a SharePoint calendar In the menu bar above the calendar, click on the Actions button, then select Connect to Outlook Click Yes when Outlook prompts you to connect to the Calendar You can now view the SharePoint calendar from the Outlook Calendars view. It will appear under your Other Calendars section of your Navigation panel in Outlook, so you can view them in the future by checking the check box next to their name.