The Peloponnese, Present Day
Not so Strait and Narrow
The action in the Jason, Leo, and Piper chapters takes place aboard their ship, the Argo II, as they make their way to Athens. See this map? It's as easy as traveling that little strait, the Corinth strait, to get there. A snap, right?
This is an adventure story, so in the first few chapters, Jason and friends realize that the strait is filled with traps which equal certain death. Instead, they have to go all the way around—and even that way isn't completely safe, and they get to have a few adventures along the way.
The Greek and Roman Globetrotters
Reyna and Nico teleport via shadow-travel to a few different locales with the Athena Parthenos—Pompeii, Portugal, Puerto Rico, exotic South Carolina—all on their way to Camp Half-Blood…which you may remember from Percy Jackson's first set of books. Although they mostly fight monsters, they also get to see a few sights along the way, like a temple made out of bones (no thanks) and the Barrachina restaurant, birthplace of the piña colada. We'll take two.