Fell tales and fell fates, three times three:
He dreamt an old dream, of ¹three knights in white cloaks, and a ²tower long fallen, and ³Lyanna in her bed of blood.She dreamt an old dream, of ¹three girls in brown cloaks, a ³wattled crone, and a ²tent that smelled of death.
He dreamt an old dream, of a ²hovel by the sea, ¹three dogs whimpering, a ³woman’s tears.
Lots of matches there, lots of omens, lots of loss: three prophetic dreams of yesteryear that lighted fools the way to dusty death, each leaving ought but broken bones and unquiet ghosts.
The “how” is the easy question to answer, but it is not the interesting question. The interesting and much harder question is the “why” part of it.
The “how” is easily explained: the Lord of Greywater Watch was there. You know, that little guy who moves his castle around all the time so nobody can find it? Howland Reed merely used the earth-moving magic he learnt on the Isle of Faces to make the Tower of Joy come tumbling down. There is no mystery here: the magic that smashed the Arm of Dorn and made the Neck would have had no trouble with a little bit of stonework.
The truly interesting question that nobody answers satisfactorily, the real mystery that needs solving, is why was it so bloody important that that Tower be razed? Why was it imperative that no other person ever find it intact after Ned had left? What thing or fact or circumstance or knowledge was thereby forever hidden by reducing the Tower to dust and rubble?
Is this how Howland Reed saved Ned from the Sword of the Morning, the finest knight Ned had ever seen? Did the little crannogman dissolve the very floor beneath Arthur Dayne’s feet during the final fateful battle? Would Ned have found that a dishonorable way to have survived? It might be so, but that doesn’t seem a good enough excuse to destroy the Tower, not by itself.
Could there have been something else than this? What about those who were buried beneath the cairns, cairns of heavy boulders that no one would ever tear apart to look beneath? Why would their corpses need hiding? Wouldn’t they just have burned them if that were all it was?
The most likely answer must surely be that Jon’s secret identity was somehow hidden by this action. The Tower must have been brought down to somehow save young Jon’s life — and Ned’s life too, since he would have lost his head for being a traitor to Robert by hiding the last Targaryen heir to the Iron Throne, the ones the sworn Kingsguard had just given their lives to protect. They would have tried to make Jon king if any had lived, so they had to die to keep the secret and allow Jon to live a life where he would not be forced onto the Iron Throne, or killed just for being who we was.
But even that shouldn’t have required the Tower’s destruction. What was in there that required destroying the Tower to keep people form learning something? Was razing the Tower somehow part of Ned’s promise to his dying sister?