That event has not yet happened.
It's as real as that alien sighting in Jeruselum.
the first vampire sighting was in 0001bc.
I think it has to be the Roswell, NM crash site in 1947.
That was prior to written history so there is no record of the first sighting.
An alien report sighting can be reported to the local media or to NASA. Often times sightings can be found to be a fraud and will be put aside for more important tasks.
the first sighting was in 1,000,907 BC so yeah that's when it occured.
One of the most well documented UFO sightings occured in 2005 in Xapala, Mexico.
Well a Kraken is a mythological creature, so there never was a first sighting of something that didn't exist. But it was seen in Pirate's of the Caribbean ;)
565 AD
No recognizable pattern to locations or time; however, when there has been a sighting somewhere there often are more close by and soon afterwards.
The first "sighting" of Stonehenge was when it was built. Since that time it has remained in the same location, which has been common knowledge. It has never been lost or rediscovered.
no