This verse is describing the death of Athaliah, the queen who had seized the throne of Judah and ruled through treachery and violence. Let's break it down:

"So they made way for her.": This indicates that the people who were involved in the plot to overthrow Athaliah (priests, Levites, and commanders) cleared a path for her to be taken out of the temple area. They likely wanted to avoid bloodshed within the sacred grounds.

"She went to the entrance of the horse gate to the king’s house;": This specifies where Athaliah was taken. The "horse gate" was likely a gate near the royal stables or used for transporting horses. The "king's house" refers to the royal palace. This was a public place, but still associated with the royal power she had usurped.

"and they killed her there.": This is the most direct part. Athaliah was executed at the entrance of the horse gate. This action signified the end of her illegitimate reign and the restoration of the Davidic dynasty.

In Summary: The verse depicts Athaliah being led away from the temple, to a location near the palace grounds, where she was executed as part of a coup to restore the rightful king to the throne. The location is significant because it marks the transition from religious sanctuary to a site of royal power and the end of Athaliah's reign.