Something like this has also happened to me when in holiday in Spain. I was looking around nice buildings open to the public, and entered one that I later found out happened to be a university. Walking around I entered one very well decorated hall, also because it started to rain and had to wait somewhere until it passed. To my horror, more people started coming in as well and I realized I was in for some sort of book or thesis presentation on the subject of Spanish language on the Balearic islands.

I barely speak Castilian Spanish (the more common one) and it was instead in Catalan Spanish, so I didn't understand a word, but stayed for the 1-2 hours it took, clapped, and skipped the handshakes/signing part of it.

Many years ago I took a look at my high school senior yearbook for the first time since I’d graduated. I spotted a note from a girl asking me to call her after graduation.

I didn’t remember the name (first name only), and the phone number was from a different town 20-30 miles from my high school. Unfortunately I don’t believe I still have the yearbook, so it shall forever remain a mystery. I literally had, and have, no clue.

What a classy move to quietly ride it out and avoid doing anything to distract from the ceremony.

This reads almost like a scene from the IT Crowd.

this happened to my mother-in-law, where she was the crasher.

in North London there is a large Turkish centre that hosts Turkish weddings. She was invited to a wedding there.

Traditionally, the bride and groom stand in the centre of the room and then family members lineup next to them all in a procession.

As you enter the room to reach the bride and groom, you must shake the hands in turn of all of the people in the procession.

When my mother-in-law eventually got to the bride and groom, they realised that the bride and groom were strangers. The accurate wedding was taking place upstairs at the same time.

There are multiple wedding venues in that particular Turkish Centre.

There was an even crazier story when someone was fired from Apple, but still kept coming to the office to work on their project for free for like half a year before someone noticed.

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