There are many Holiday and Sports calendar feeds available on the internet that you can subscribe to in BusyCal or OS X Calendar, but many of them are not kept up-to-date. We provide a list of many common holiday and sports calendars on our site that you can subscribe to.
We also maintain our own US Holidays calendar that is available in three flavors with no graphics, small graphics, or large graphics. You can subscribe to one of these new US Holidays calendars by clicking one of the links below.
BusyCal has the ability to display graphics. We include graphics for many of the major holidays on the US Holidays calendars in either small and large sizes. Here's what the Christmas holiday looks like with no graphics, small graphics, and large graphics in BusyCal. See BusyCal Graphics for more info.
BusyCal displays holiday names in gray italicized text on the bottom of the day cell to help them stand out from other all-day events. The Info Panel provides an "observed" checkbox for each Holiday event. If you select this checkbox, the date will be displayed in red on that date. See BusyCal Holidays for more info.