Add a Calendar
The Calendars module is used to manage holidays.
Typically, only a single calendar needs to be defined. However, if a system crosses multiple cultural or geographical boundaries, or consists of multiple sites, then multiple calendars may be needed. Because holidays can vary from year to year, a calendar needs to have each holiday defined for each year. It's best to define all known holidays in advance for the expected lifetime of the system.
Go to Configuration > Calendar.
Select Add.
Enter a name for the calendar.
Select Holidays as needed.
Enter the information about the specific holidays that you want the calendar to recognize.
Press Save and Close.