Where is the ark of the covenant?

The ark of the covenant no longer exists. It was likely destroyed by Nebuchadnezzar around 600 BC when he destroyed the temple in Jerusalem. The Lord does not want Israel and the world to remain focused on the ark now that the Messiah, Jesus Christ, has appeared to fulfill everything the ark represented. As the Lord spoke through Jeremiah:

Jer. 3:16 “It shall be in those days when you are multiplied and increased in the land,” declares the LORD, “they will  no longer say, ‘The ark of the covenant of the LORD.’And it will not come to mind, nor will they remember it, nor will they miss it, nor will it be made again."

Scripture quotations taken from the (NASB®) New American Standard Bible®, Copyright © 1995, 2020 by The Lockman Foundation. Used by permission. All rights reserved. www.lockman.org