Dimensions of the Past is an expansion to Quake and requires the original version to play. It is created by MachineGames Sweden to celebrate the twentieth birthday of Quake and also with a promotional goal as the developer was working on Quake: Heroes at the time. It contains nine single-player levels, a start map for the three difficulty levels (with a fourth nightmare difficulty level hidden there as well), a secret map and a deathmatch arena. There are also three rolling demos with gameplay from the levels when the game is launched.

There are no new game elements such as textures, enemies and weapons, only the new levels. These are aimed at advanced Quake players. Even at the lowest difficulty level there are often many enemies that spawn at once, tight rooms to fight, and ammo is scarce. Each level has around five secrets and finding these is often required to get additional ammo or power-ups needed to clear the rooms.