What is the first book in the Heroes of Olympus book series by Rick Riordan?
The Heroes of Olympus is a collection of fantasy novels by Rick Riordan that collectively form a sequel to Percy Jackson & the Olympians. The first book of the series was The Lost Hero was published on October 12, 2010.
Order of Books:
1. The Lost Hero
2. The Son of Neptune
3. The Mark of Athena
4. The House of Hades
5. The Blood of Olympus
Riordan introduces Roman mythology in his sequel series as well as several new characters. The final entry in the series, The Blood of Olympus, was published on October 7, 2014.