

Act I is similar to the original Diablo the Rogue Encampment is a simple palisade fort, with plains and boreal forests making up the wilderness area, and the Monastery resembles the typical medieval fortress. Act II mimics Ancient Egypt's desert and tombs Lut Gholein resembles a Middle Eastern city and palace during the Crusades. Act III is supposedly based on the Central American jungles Kurast is inspired by the lost Mayan civilization. Act IV takes place in Hell and is the shortest, with just three quests compared to the other Acts that have six. The Lord of Destruction expansion adds the fifth chapter Act V which continues the story where Act IV left off. Act V's style is mainly mountainous as the player ascends Mount Arreat, with alpine plateaus and icy tunnels and caverns.

Occasional portals can take the player to dungeons in Hell (seen in Act IV) for extra monsters and experience.

After reaching the summit of Arreat, the player gains access to the Worldstone Keep (whose architecture may be reminiscent of Angkor Wat and other Hindu temples).
