I found the Photo Challenge this week to be very challenging, because I had too many ideas and too many photos to choose from (luxury problem). After having opted out a bunch of photos, I ended up with these photos shot at a secret location somewhere in Midgard (Miðgarðr as it is called in Old Norse. Meaning Middle-Earth, the home of the humans). What you see on these photos is the most common, or most known, example of the optical phenomenon called dispersion:

This rainbow is more like a spray bow, created by the mist of the waterfall
This rainbow is more like a spray bow, created by the mist of the waterfall

The Rainbow
Yes, a rainbow is an example of the optical phenomenon called dispersion. A pot of gold is said to be hidden at the end of it (I’ll get back to that).
In Norse Mythology, a rainbow called the Bifröst Bridge connects the realms of Ásgard and Midgard – the homes of the gods and humans, respectively. And that’s the reason for the secrecy regarding the location of this photo: ’cause we don’t want people to be able to travel freely between the homes of the gods and the humans do we? Not only the Vikings, but also the Greek-Romans, considered the rainbow to be a connection between the earth & heaven.
Historically the rainbow has had some kind of mystical or supernatural explanation in nearly all the different superstitions during time: Chinese mythology, Hinduism, Armenian mythology, the Australian Aboriginals, et cetera, et ceterea.
Gilgamesh
For example in the ancient Epic of Gilgamesh the rainbow is the “jewelled necklace of the Great Mother Ishtar” that she lifts into the sky as a promise that she “will never forget these days of the great flood” that destroyed her children. (The Epic of Gilgamesh, Tablet Eleven). Now, if you take a closer look at this story, you realize that it is almost the exact same story that you’ll find in all the Abrahamic superstitions: they’ve just changed some minor details, but basically plagiarized the whole thing.

The Leprechaun & the Canterbury Tales
I’m not quite sure how this story has originated, but it might have been som drunk Irish that owed someone a whole lot of money, and in order to save his own ass came up with this: the end of the rainbow is the Irish leprechaun’s secret hiding place for his pot of gold.
Good thing I don’t believe that story either, because when this photo was shot we were 3 persons present, so chances are I could have ended up like one of the three drunken men in “The Pardoner’s Tale” (one of The Canterbury Tales by Geoffrey Chaucer). Or I would have drowned in an ice-cold river, trying to reach the pot of gold.

“The Pardoner’s Tale”
Just in case you don’t know the story and you won’t bother to look it up, I’ve copied this summary of The pardoner’s Tale from Wikipedia:

“Three drunken and debauched men set out from a pub to find and kill Death, whom they blame for the passing of their friend, and all other people who previously have died, which they were told by the Landlord. An old man they brusquely query tells them that he has asked Death to take him but has failed. He then says they can find Death at the foot of an oak tree. When the men arrive at the tree, they find a large number of gold coins and forget about their quest to kill Death. They decide that they would sleep at the oak tree over night, so they can take the coins in the morning. The three men draw straws to see who among them should fetch wine and food while the other two wait under the tree. The youngest of the three men drew the shortest straw. The two plot to overpower and stab the other one when he returns, while the one who leaves for the town plots to lace the wine with rat poison. When he returns with the food and drink, the other two kill him and drink the poisoned wine, dying slow and painful deaths. All three have found death.”

Here’s a runner-up:

My friend Mark looking for the barn children
My friend Mark looking for the barn children

Sources
Wiki: Epic_of_Gilgamesh#Tablet_eleven. Dispersion_(optics). Gilgamesh_flood_myth.

I think fellow blogger Jake Sprinter had an important message in his interpretation. Here are other bloggers interpretations:
Weekly Photo Challenge: Hidden (maggiephotgraphy.wordpress.com
Weekly Photo Challenge: Hidden (fromundermanyhats.com)
Weekly Photo Challenge: Hidden (dailypost.wordpress.com)
Weekly Photo Challenge: Hidden (mikehardisty.wordpress.com)
Weekly Photo Challenge: Hidden (hereandthere5.wordpress.com)
Weekly Photo Challenge: Hidden (andreadreamin.com)
Weekly Photo Challenge: Hidden (directionallyimpaired.wordpress.com)
Weekly Photo Challenge: Hidden (jakesprinters.wordpress.com)
Weekly Photo challenge: Hidden (shomabhagwat.wordpress.com)
Weekly Photo Challenge: Hidden (hurtlingtowards60.wordpress.com)
Weekly Photo Challenge: Hidden (snapsbytwinkle.wordpress.com)
Weekly Photo Challenge: Hidden (blackcatsramblings.info)
Weekly Photo Challenge: Hidden (ramblingsofatimetraveler.wordpress.com)
Weekly Photo Challenge: Hidden (jobryantnz.wordpress.com)
Weekly Photo Challenge: Hidden (nandinidhiman.wordpress.com)
Weekly Photo Challenge: Hidden (amarnaik.wordpress.com)