The third in the praise trilogy, we have now the emphasis on Zion. We’ve seen God as Protector, as King, and now His earthly capital reflects His glory.
Depending on the particular translation, there is reference to Mount Zaphon or simply the North. Scholars say it is the modern Mount Aqraa, standing near the Mediterranean Sea in far southern Turkey, near the border with Syria. In this context, the reference is not so much a place or a direction, but a symbol of the ancient mythological mountain of the gods. It looms large in Ugaritic legends as the place the gods gathered. In Hebrew thinking, whatever gods might gather there were subject to Jehovah.
We can but guess what ancient Jerusalem looked like when this was written, but we do know the place was expanding quickly under David. It served as a prominent landmark and quickly drew traffic as the royal city of what was then the strongest kingdom in that part of the world. Should we imagine this was published anytime after Solomon built the Temple, that would have been a striking image from a great distance. There is no literal comparison with the topography of Mount Zaphon, but Zion was a magnet for people passing through, not to mention a proud symbol of the Hebrew people. If you are going to seek out an earthly manifestation of the divine, this is the right place.
Thus, we are treated to Hebrew hyperbole about kings assembling only to be stunned and cowed by what they see. Come and see the mighty fortress and throne of our God whose feats are world renowned! It was only just that people at the far reaches of known lands would worship Him. You would naturally expect the residents to be proud and happy in the shadow of their God.
So the psalmist invites everyone to see the sights, to view it from every angle. Then come inside and inspect the protective features. Go and take to the farthest lands stories of this mighty throne of the Lord of all Creation.