Reeves shared the first photo taken on the filming set on his Twitter.
The picture showed a silhouette of two actors on a lonely beach. One person stood while gesturing another person on horseback.
The director captioned it, "#It has begun. @ApesMovies."
He also confirmed that Michael Giacchino would return to compose scores for "War of the Planet of the Apes".
Starring Andy Serkis, Gabriel Chavarria, Steve Zahn, Amiah Miller and Woody Harrelson, "War of the Planet of the Apes", the new installment of "Planet of the Apes" movie series, is scheduled to hit theaters on July 14, 2017.