Oh, the Irony

We notice this quote in a story this morning about a couple of newlyweds who put their wedding vows in a bottle and tossed them into the waves. The couple that found the message had been married on the same beach, and sent a letter to the newlyweds:

The letter read, "We thought you would want to know where your message in a bottle ended up! We picked it up on the beach between Pentwater and Silver Lake on Sept. 19. An ironic note, we were also married on the beach! Here in Michigan by Pentwater. Even more ironic, it was on August 18, 1979. We wish you both the best of luck in your new lives together."

The actual irony here is the use of irony. There is no irony in the situation whatsoever. Irony is incongruity, or where contradiction of some sort causes humor. The shared wedding dates are a coincidence.