The Longitude Is Zero And So Is Their Understanding

I work at a popular London tourist attraction, on one of the entrances. I get approached by a visitor who is struggling to find the main part of our attraction: the Prime Meridian Line.

Visitor: “Excuse me, can I ask you a question? Where is the Meridian Line?”

I point to where it is.

Me: “You see where the different paving stones and metal tiles on the ground are? Where everyone is taking photos? That’s the Meridian Line.”

The visitor wanders over to a point closer to the line so he can see it better. I continue to deal with other visitor enquiries until he wanders back over, looking puzzled.

Me: “Hello again, sir, how can I help?”

Visitor: “I still can’t see the line. Could you come up and show me?”

I walk over to the better viewing point with him and begin explaining again.

Me: “You see the tree over there? It’s the metal line underneath the tree.”

Visitor: “Ah, so the Meridian Line is the tree?”

Me: “…”

Related:
No Fortitude For Longitude, Part 15
No Fortitude For Longitude, Part 14
No Fortitude For Longitude, Part 13
No Fortitude For Longitude, Part 12
No Fortitude For Longitude, Part 11