Event covers are decorated, stamped and canceled commemorative
envelopes. They are created to celebrate an event or note an
anniversary. The design (called a "
cachet") is generally placed on the left side of the envelope (although there are also "all over" cachets). It explains what is being commemorated on what date, and generally also includes an illustration page.Ideally, the stamps used relate to the celebration (for instance, space stamps for a shuttle launch). Cancels are either obtained in the city of the event (such as
Kitty Hawk for the
Wright Brothers first flight anniversary) or, for larger quantities of envelopes, from a special cancellation unit maintained by the Postal Service in
Kansas City, Missouri. If a special cancellation (one with a design) has been created for the event, you can generally only receive that cancel from the local post office.
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A cachet dealing with a specific event and the postmark tied into the date of the event.