Isaiah 40:4

4 Every valley shall be raised up, every mountain and hill made low; the rough ground shall become level, the rugged places a plain.

Read Isaiah 40:4 Using Other Translations

Every valley shall be exalted, and every mountain and hill shall be made low: and the crooked shall be made straight, and the rough places plain:
Every valley shall be lifted up, and every mountain and hill be made low; the uneven ground shall become level, and the rough places a plain.
Fill in the valleys, and level the mountains and hills. Straighten the curves, and smooth out the rough places.