Beyond The Ice Wall [best]: The World

When they surfaced on the other side, Pip was the first to break the silence.

It rose from the bruise-colored sea five miles away: a tower woven from what looked like fossilized lightning. It had no angles, only spiraling curves that hurt to follow. At its base, the water churned in a perfect circle, and from that circle rose a sound—not a roar, but a single, clear note, like a cello string plucked by a giant. the world beyond the ice wall

And the universe beyond the wall is listening. When they surfaced on the other side, Pip

For the brave soul wanting to see this for themselves, the routes are few and dangerous. but a single

What specific features define this hidden realm?