And I looked, and behold: See the comments on 2 Esd 11.2.

He carved out for himself a great mountain, and flew up upon it: Compare Dan 2.34, 45 (see also Rev 14.1). He carved out for himself a great mountain may be rendered simply “he carved out a high mountain” (similarly Good News Bible). The phrase for himself will be unnecessary in many languages. In those languages that cannot talk about a human flying, the clause flew up upon it may be translated “soared up into the air to the top of the mountain” (see the comments on 2Esdras 13.3). But in others languages “fly up on it” (Good News Bible) or “flew to the top of it” (Contemporary English Version) will be natural style.

Good News Bible provides a helpful model for this verse.

Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on 1-2 Esdras. (UBS Helps for Translators). Miami: UBS, 2019. For this and other handbooks for translators see here.