Game of Thrones question regarding the Wights/Zombies

[Samtemdo8_v1legacy]

So in the end, the answer is no, the Wight's can't walk underwater like in Curse of the Black Pearl?

But what about the White Walkers making an Ice Bridge around the wall?

Again, like we said, the Wall is not just a physical barrier. Theres old and powerful magics in it and I highly doubt they can be circumvented by just taking a slight detour. Mostly because if they could, the White Walkers would have already done it

I still believe it was the White Walkers who made the Wall and Bran the Builder was a made up legend to cover the real builders of the Wall.

Why though? Why would they want to build a big ol' wall like that? And you argue that it can't have been the humans of the time since you didn't think they had that kind of "architecture-mancy"...but neither do the White Walkers. When have we ever seen them build anything let alone a big magic wall?

Have you not seen the Land of Always Winter?


Allow Alt-Shift X to explain (play the Video at 13:31 about the Wall itself):

 

[Palindromemordnilap_v1legacy]

Have you not seen the Land of Always Winter?

Some spiky bits of ice in a scenery of frozen environment. Not a castle, not a fortress, not anything like the construction you'd need for the Wall. My point stands; if you're going to insist that nothing humans have done matches the Wall, neither does anything the White Walkers have done.

Allow Alt-Shift X to explain (play the Video at 13:31 about the Wall itself):

Why build it out of ice? Because its the only thing the White Walkers can't freeze through. They bring the temperature low enough they can shatter metal, its the first trick we see them do in both books and show, you think regular construction materials are going to keep them out for long? A wall of stone will crack and crumble as moisture and ice works its way through fissures and cracks, but a wall of ice only repairs itself when subject to those conditions. Yeah its going to be hard (though honestly getting local, lighter ice is going to be easier than ferrying heavier stone from further away) but you know whats harder? Dying when an army of ice spirits and their zombie horde come invading.
And speaking of that zombie horde, you've ignored one of Melbourne's points: If its built by the White Walkers, why does it specifically prevent their main choice of servant from crossing? Humans can go through the various gates or indeed just go round one of the edges, but anything undead is completely barred. Coldhands spells that out for us pretty specifically. Bit of a design flaw if its White Walker built, don't you think?

 

[jademunky]

Dunno, is a corpse naturally buoyant? I seriously am unsure.

If it is, then they should probably be able to swim after a fashion. If not, no must make do with plodding along the bottom of the river/ocean/lake.

Now why, in either case, they don't just go around the wall? Because plotholes, also because they breathe through their skin.

 

[Silvanus]

Have you not seen the Land of Always Winter?

This is a scene that exists only in the show. Nothing approaching this is shown in the book series.

Allow Alt-Shift X to explain (play the Video at 13:31 about the Wall itself)

This is an argument from incredulity, really: he cannot imagine how the First Men managed to build the Wall, and so he concludes that it cannot have been them.

This isn't a rational reason, honestly. Brandon the Builder was renowned as an architectural genius, and has accomplished numerous other incredible feats of engineering (such as Storm's End). The Long Night supposedly lasted for a full generation, meaning that he had a good long time to work, and this is quite possibly with giants as his disposal. What Brandon could have accomplished in that time is unknown, and is likely to be incredible.

The Wall specifically prevents the Others and the Wights from passing through it, and does not have the same effect on humans. It features a weirwood door deep below the Nightfort, allowing passage only to sworn brothers of the Night's Watch. It is human-built, and serves humanity.

 

[Baffle]

Dunno, is a corpse naturally buoyant? I seriously am unsure.

As I understand it, though this may be urban myth stuff, corpses become bouyant when the gases of decomposition build up and cause them to rise to the surface. As I understand white walkers are raised pretty quickly, I guess that isn't the case.

 

[Terminal Blue]

They are purely humans, and nothing more.

True, but the idea of magical bloodlines is pretty well established in ASOIAF, at least in the form of in-universe mythology.. and it's not a coincidence, I suspect, that literally all of the people known to have dragon dreams are Targaryens or Blackfyres, just as I suspect it's not a coincidence that several of the Starks are skinchangers or have dreams about wolves.

But of course, even if true, this doesn't make them "not human" as magical abilities are a feature humans can possess in ASOIAF. Most magic users we encounter directly or indirectly are just random people and seem to have no exceptional ancestry or bloodline, Valyrian or otherwise.

If anything, Asshai is just as if not more associated with magic in the setting as Valyria, and Asshai is supposedly where Danaerys' dragon eggs came from. Again, I suspect that's not a coincidence.

 

[Dudemaker]

I never thought they could "swim" as such. That they might cross water to get around the wall never struck me as a valid way for them to invade.

As far as the books are concerned I always imagined it would turn out that the wights/white walkers had the horn of Joramun, because of how Ygritte told Jon Snow that they (the wildlings) never found it.
Regarding the show... when Bran was marked by the Nights King, allowing the white walkers to breach the ward around the 3 eyed raven's cave, I thought that Bran would be their "passport south" so to speak once he went south of the wall again. The mark on his arm negating the wall's power as it had with the cave.
Once season 7 aired i noticed how the opening map showed ice east of the wall where the narrow sea had previously been so then i thought they would simply walk around Eastwatch over the frozen sea.

The OP's question does bring up another point though...
Are the white walkers now a threat to the whole world? Or just Westeros?
How are they supposed to threaten Essos & the rest of the world unless they can cross water?
Does winter hit the entire planet?