"The Mark of Athena" mentions the many conflicts between the Roman and Greeks over the years, a notable occurrence was the Civil War, which apparently was started as a major conflict between both the Romans and Greek demigods. This book however offers a new land that the seven demigods of prophecy must travel to, the ancient lands where the Greek and Roman empires were originally located. The daughter of Athena, Annabeth, must follow the mark of Athena to find a lost artifact, taken from ancient Athens when the Romans invaded that can unite the Greek and Roman demigods.
"The Percy Jackson and the Olympians and Heroes of Olympus" book series is definitely a must read series for any enthusiast of Greek or Roman mythology. This book series offer a modern twist on many of the old myths from Greece and Rome. Their author, Rick Riordan, is personally one of my favorite authors; he has a way of writing that I find unique. In his more recent series he has written from a third person point-of-view that takes the form of the most relevant character's perspective. For anyone that is interested in more than just Greek and Roman mythology, he also has a book series called the "Kane Chronicles" for anybody interested in Egyptian mythology.