about the swords of dalamud

[Myrhn]

Ragnarok isn't the big sword like thing that falls from the sky before bahamut got out?

[Jeykama]

Seems obvious to me that T2-4 takes place on one of the swords. Beating T1 activates a hexagonal elevator that descends to T2. T2 takes place atop the "crossguard" of one of the swords, just watch the intro video panning across it and looking up the hilt. After beating ADS you descent to a path leading inside the crossguard, making me believe T3 occurs within the crossguard itself. T4 is a 7-minute joyride down the blade on an elevator. The elevator descends to a stop at the hand (T5). How we end up in Thanalan going straight down? dunno.

However, T1-5 all take place in enormous caverns coated in corrupted crystals. I can't help but think that those caverns are cysts formed by the planet to contain the corruption (i.e. bahamut's parts + dalamud bits) within, and the bubbles we see above ground are incomplete formations of a cyst due to the respective object being only partially buried. Most of the swords appear to be featureless javelins that could have punctured the surface with very little initial trauma, leading to very little crystal malformation so we wouldn't even know something was underfoot.