Hollow Bastion is a significant location in the Kingdom Hearts video game series. It serves as a central hub for various characters and events, featuring a blend of medieval architecture and magical elements. The castle is known for its intricate design, including towering spires and vast chambers, which reflect its rich history. Originally a peaceful place, Hollow Bastion becomes a battleground for the forces of light and darkness. It is home to key characters like Riku and Kairi, and plays a crucial role in the overarching narrative of the series, symbolizing the struggle between good and evil.