2. Right-click My Calendars (or any other calendar group's heading) on the left-hand side of the screen to display the options for that group.
3. Hover over Add Calendar and select From Internet... in the sub-menu.
4. Type (or paste) the URL for the internet calender in the "New Internet Calendar Subscription" window that appears and click OK.
5. Click Yes to subscribe to this internet calendar and add it to your list of calendars.
The internet calendar now appears in your list of calendars within the selected calendar group. In general, you will only be able to rename, move, and change the color of internet calendars you've subscribed to in Outlook 2013 because they are often managed by someone outside our organization.