One of the more popular features for Outlook’s calendar is the capability to add your country or region’s holidays into your calendar. This way, you’ll never miss the next holiday.
Adding holiday items to your calendar is easy:
1. From the Tools menu, click Options, then click Calendar Options.
2. Click the Add Holidays button under Calendar options.
3. Select the check box next to your location, and any other location you might be interested in, and then click OK.