Here is the passages from Cold Days describing the build; pages 169-169
First thing, if he did indeed travel in time to build the Island, Merlin arrived via the Nevernever
Then a ribbon of light maybe eight feet long split the air vertically. The light broadened until it was maybe three feet wide, and then a figure appeared through it. I recognized the signs---someone had opened a Way, a passage from the Nevernever to the island.
This was Merlin, I bolded the last because this is important information Harry is going to need now to travel to the island and back. It could be the one Rashid uses or another.
The grey-clad figure became a blur. It walked about waving its arms, and directed oceans of energy here and there, settling them all in and around the substance of the island itself.
This continues for some time apparently because on the next page;
A LOT OF TIME PASSES.
Here is the important bit about it's building
"Merlin didn't build the prison five times," Bob said. "He built it once. In five different
times. All at the same time."
This blew Harry's mind. Bob explained further;
"Look, a mortal jail is built in three dimensions,right? Merlin built this one in four, and probably in several more, though you can't really tell whether or not he built it in a given dimension until you go there and measure it, and the act of measuring it will change it.
Here is another interesting bit, the enchantments, I will only copy the first line or two, but you get the picture it goes on to page 170 talking about enchantments on top of enchantments..
The shot zoomed out rising up to give a top-down view of the island,which became a blurry shape. A familiar five-pointed star blazed itself across the surface of the lake, its lines so long that the pentagon shape at its center enfolded the island entirely
It goes on and repeats thousands of times over in different directions over different dimensions.
Okay, I bolded this bit because what does Harry wear around his neck? What does Thomas and Eb wear? A pentagon. Now a pentagon maybe a standard thing in this kind of enchantment, and the fact that the Dresden family also wear one is a coincidence.. Or maybe not so much, if you couple that with the journals in Eb's possession that have been handed down for centuries and hinted to go back as far as Merlin... One more connection, Merlin emerged from the Nevernever, he had opened a Way, Margaret spent a lot of time in the Nevernever, and oh just happens to have a jewel that is the gps to all the Ways, which Harry also inherits from her.. Oh and one final intriguing bit, in Small Favor, though he'd had never stepped foot on the island before, he felt like he had walked on it's steps before..
So here goes, as many of us suspect the Dresden family are direct decedents of Merlin. Merlin's decedents have always acted as Wardens of the island. This is why Alfred accepted Harry in the first place. It could be that the Council is ignorant of the Dresden ancestry, so instead of appointing Eb it's Warden, they appoint Kemmler, that is where things went wrong. Or could Kemmler be related somehow to the Dresdens, thus descended from Merlin as well? Or was that a lie to get the job?
But I digress, Eb also says in his journal that he trusted Harry with the job of Warden,
but then he trusted Maggie as well. Curious remark, if he hadn't made such a mess of her apprenticeship leading her to rebel, would Margaret have gotten the job? Could that have added more fuel to the fire of the Council's fears of a dark lord being Warden of the island? So they thought it better that it remain vulnerable than another Warden?
Finally, Harry's feeling that he'd been there before, yeah, I know how Luccio explained it, but put on your tin hats guys.. Harry felt like he'd been there before, because he had, he is Merlin. That will become more apparent by the end of the series, another little bit that may point to this is the image Harry has of himself as he battles Sharkface in his head..
page 417 Cold Days
I lifted my right arm to the frozen sky and shouted, wordless and furious, and a bolt of scarlet lightning flashed from the seething skies. It smashed into my hand and then down into the earth. Frozen dirt sprayed everywhere, and when it cleared, I stood holding an oaken quarterstaff carved with runes and sigils, as tall as my temple and as big around as my joined thumb and forefinger.
Harry, starchild, Merlin reincarnated..
