Prestonpans was famous for mining, yes, but before that, it was known as the site of one of the most notorious witch hunts in all of history. It predated the Salem Witch Trias, and was the inspiration for the 3 witches in Shakespeare's "Macbeth." It is the story of the 81 Witches of Prestonpans. Annemarie Allan wrote a book on the topic if you'd like to learn more (click the image), but here's the summary.
The town of Prestonpans goes back to the 1100s, named for the salt pans monks used to cook salt from the sea water for trade. Salt in those days was as valuable as gold and many people grew very rich from it. In the 1500s, the Bailie of Tranent, David Seton coveted the riches of his kinswoman, Euphemia MacAlzean. How to get her money, how?
He had his servant, Gelie Duncan accuse MacAlzean of witchcraft.
Duncan also accused Agnes Sampson and John Cunningham, the local schoolmaster. Sampson was tortured into naming others, and hence, the witch hunt began. It reached its peak when King James IV (a.k.a. King James I of England) hit violent waters on the Firth of Forth. He said witches had cursed his passage, and more people (85% women) were accused, tortured and murdered.
Gossip spread quickly. It was said that hundreds of witches gathered at the Fiery Hills of Acheson's Haven, where the devil spoke with them directly. This is what that coven was illustrated to look like - notice the devil on the left. (img: Wikipedia)
Although the killings stopped, the accusations didn't. The last person convicted under the Witchcraft Act of 1563 was Helen Duncan in 1944. The Witchcraft Act was finally repealed in 1951 under Sir Winston Churchill. Here is a brief local article about the region's history with witches.