Portal:Dungeons & Dragons/Selected rulebook/6

Expedition to the Barrier Peaks is a 1980 adventure for the Dungeons & Dragons roleplaying game and was written by Gary Gygax. The 32-page adventure bears the code S3 ("S" for "special") While Dungeons & Dragons is typically a fantasy game, the adventure includes elements of science fiction and science fantasy. It takes place on a downed spaceship; the ship's crew has died of an unspecified disease, but functioning robots and strange creatures still inhabit the ship. The player characters fight monsters and robots, and gather futuristic weapons and colored access cards necessary for advancing the story.

Expedition to the Barrier Peaks was first played at the Origins II convention in 1976 where it was used to introduce Dungeons & Dragons (D&D) gamers to the science fiction game Metamorphosis Alpha. In 1980, TSR updated the adventure for first edition Advanced Dungeons & Dragons rules and published it. The adventure was never updated for any later rules systems, but a Wizards.com article did provide a conversion to Future Tech. It included a separate booklet of illustrations, some of which were in color. The adventure is an old time favorite of many Dungeons & Dragons fans, including Stephen Colbert. It was ranked the fifth best Dungeons & Dragons adventure of all time by Dungeon magazine in 2004, and received positive reviews from White Dwarf and The Space Gamer magazines. The other adventures in the S series include Tomb of Horrors, White Plume Mountain, and Lost Caverns of Tsojcanth.