…There was a pillar rising to the right. At its top was something globe-like and glowing. Perhaps fifteen feet lower, another such formation occurred on the left. Beyond that, it seemed there was another one on the right and so on.

When we entered the vicinity of the thing, the waters grew warmer and the stairway itself became clear: it was white, shot through with pink and green, and resembled marble but was not slippery despite the water. It was perhaps fifty feet in width and there was a wide banister of the same substance on either side.
Nine Princes in Amber