Why does Annabeth want to visit the St. Louis Arch?

Annabeth loved architecture.... and she wants to be an architect.

Annabeth craned her neck to see the Gateway Arch, which looked to me like a huge shopping bag handle stuck on the city.
“I want to do that,” she sighed.
“What?” I asked.
“Build something like that. You ever see the Parthenon, Percy?”
“Only in pictures.”
“Someday, I’m going to see it in person. I’m going to build the greatest monument to the gods, ever. Something that’ll last a thousand years.”