Open-world video games bear the impossible promise—offering compelling, enjoyable open-endedness and freedom within the constraints of what is, by necessity of the medium, an extremely limited set of possible actions. These games provide a list of (predominantly violent) verbs that's minuscule in comparison to the options you would face in identical real-life situations. Yet, we can't get enough of them.

In spite of their many obvious failings or limitations, we've been losing ourselves within open worlds for some 30-odd years. Today, nearly every big release is set in an open world. We delight in their unspoken possibility and shrug at their quirks.

Those quirks, by the way, are not merely a consequence of current technology. The oddities of modern open-world games have origins in the games that came before. We're not talking about just the earlier Grand Theft Autos—even the first GTA built on the foundations set by more than a decade of prior open-world games.

Before we get started, a quick note on definitions: open-world game design exists on a spectrum. Many titles have aspects of it, like Chrono Trigger with its eon-hopping adventure or the Tomb Raider reboot and its capacity for backtracking and exploring unlocked areas of the map. But to really classify a game as open world, it's got to be about freedom. There should be a sense that, within the rules of the game world, you can do anything at any time while freely moving about the space. It's essential for true open-world games to offer the freedom to decide when to do things, which by extension means a freedom to do things other than moving on to the next main story beat. It's admittedly a fuzzy line, but it's not worth fretting over difficult fringe cases. As with all previous game genre histories on Ars, this adventure is more about highlighting the games that are notable, in some sense, to the evolution of the genre at large.

Progenitors

Amazingly, open-world games can be traced back to the days of mainframes—namely, to the 1976 text-only game Colossal Cave Adventure for the PDP-10. Adventure at its core wasn't much different to the GTAs, Elites, and Minecrafts of today: you could explore, freely, in any direction, and your only goals were to find treasure (which is scattered throughout the cave) and to escape with your life.

Colossal Cave Adventure was a direct inspiration on 1980 Atari 2600 game Adventure. Its open world may have been sparse and populated by little more than dragon-ducks and simple geometric shapes, but its relative vastness enabled players to imagine magnificent adventures of their own making. On home computers, the influential role-playing series Ultima similarly captured the freedom, if not the liveliness, of Dungeons & Dragons. Even the first entry (1981) had no levels or "gates" to curb your wanderings through villages, towns, dungeons, and empty countryside in search of a time machine that would allow you to travel back in time a thousand years to kill an evil wizard. Later, in Ultima VI (1990), the whole world came together into a single, unified scale. Previously, towns and other places were icons on the overworld map that you transitioned into when you walked on them; now travel through and between towns was completely seamless.

Free-roaming made its way to non-RPG cities for perhaps the first time with Ant Attack (1983), a terrifying ZX Spectrum and Commodore 64 game in which you rescue your significant other and flee from gigantic killer ants through, around, over, and past M. C. Escher-like architecture.

That same year, CBS Electronics' platform-traversal game Mountain King gave players free roam on a (relatively) huge mountain. The goal was to guide your nameless stick-figure avatar around and complete three objectives: gather 1,000 diamonds, collect the golden crown (which first requires finding the flame spirit), and get back to the top of the mountain without being burned alive or assaulted by one of the many jerk bats (or cocooned and eaten by a giant green spider that lives on the bottom).

Don't fence me in

What we now know as open-world gaming took on a more definite shape this same year on the BBC Micro and its cheaper sibling the Acorn Electron (then later on nearly every other system). Elite changed everything. It was the home computer game to have in the mid-1980s—an open-ended spacefaring romp through eight 256-planet galaxies, which were fixed in their composition but cleverly generated on the fly by an algorithm in order to save on storage space. Its abstract 3D wireframe planets and spacecraft provided just enough detail to instil the appropriate sense of scale, with the rest left to your imagination. And there was so much possibility wrapped around that imagination.

You could trade a variety of goods—some common and legal, some contraband and rare—and travel deep into the game's vast void in search of whatever legendary artifacts your friends or classmates had chattered knowingly about. You could be a pirate, a bounty hunter, a government agent, an asteroid miner, a merchant, or some combination of them all. There was an antagonistic insect race to worry about, upgrades to buy, fuel to conserve and replenish, galaxies to explore, and a combat rating to improve. (This last thing was actually the stated aim of the game, but most players made their own goals.)

Elite was hardly the only important open world of the era, however. Mercenary: Escape from Targ (1985), an Atari 8-bit and Commodore 64 game, deserves just as much credit for inspiring the worlds to come.

Today, open worlds that aren't about driving tend to place high priority on shooting and stabbing. But Mercenary didn't care much for that kind of violence. You could shoot, certainly. But you didn't need to. It was impossible to die. If your ship was shot down, you'd lose it and crash unharmed to the ground. Instead, the point was to explore.

Most of the world—a war-torn planet—was empty, but at each grid point on the map you could find a building. Those buildings could be blown up to learn their names or entered and explored (on foot) from the inside. There was great humor, too: the fastest ship in the game was a chunk of cheese, a kitchen sink allowed you to pick up any object, and a cobweb could open any door.

Mercenary was amazing for the way it defied conventions. It had no scores, no requisite missions, no killing (well, not much), no emphasis on collecting stuff. The best experience was unstructured and free-form. And if you wanted to escape the world of Targ, you could freely choose sides in the war (for best results, you'd be a true mercenary and work for both the local Palyars and the invading Mechanoids).

Mike Singleton's Midwinter (1989) hinted further at the possible future of open worlds. It had the player controlling multiple characters, beginning with the local militia commander as he tries to muster an army, then with some 32 recruits, each controlled for two hours of game time, in an effort to repel an invading force in a post-apocalyptic world on a massive (supposedly 160,000 square-mile) snow-covered island. Or you could ignore that whole strategic component and find a way to destroy the enemy base single-handedly.

While not well known in North America, Hunter (1991) has one of the strongest claims to the title of GTA forebear. Its world lacked the scale of GTA, but not the variety. There were multiple vehicle types (cars, trucks, bikes, boats, tanks, helicopters, and so on), which you could hop in and out of at will and drive around like a maniac; buildings you could enter and leave instantly; guns; money; bonuses granted for killing; and an accelerated 24-hour time cycle. You could also bribe and interrogate civilians and soldiers, kill or capture wildlife, go swimming, assassinate a general, and do whatever else you could find to keep yourself occupied. It was a degree of freedom unheard of at the time, and even today there's a joy in tearing about Hunter's flat-shaded, hilly polygonal-3D archipelago.

Likewise little-known, The Adventures of Robin Hood (1991) skipped out on missions in favor of an overriding goal to turn Robin from villain to hero. In the real world, people don't pop into and out of existence depending on whether they're in your field of view. They have things to do, places to go—a mind of their own. So too in Robin Hood, which filled its world with life rather than puppets and mirages. Its people (including Robin himself) would carry on with or without your interventions.

Much better known in America, though perhaps less clearly antecedent to modern open worlds, Nintendo's 1986 action-RPG The Legend of Zelda let you complete its objectives in any order and freely explore the overworld—except for a few chokepoints that required you to track down certain items. Also by Nintendo, Metroid (1986) was one of the earliest examples of how to force an open-ended design onto core gameplay loops that are traditionally used for linear, rigid experiences. Metroid took Super Mario Bros and completely abandoned almost all of its core concepts. It was an action-driven platformer devoid of levels and scores, where you could not only go in any direction, but you were expected to do so—to explore and discover and to be ready to reshape your mental model of the game world at any moment as it gleefully defied your expectations.

Similarly, Sid Meier's Pirates! (1987) bears little obvious lineage to the modern open-world game, but it's nonetheless an important touchstone. It was a high-seas semi-historical (i.e., rooted in history, but not beholden to it) sandbox in which you attempted to guide a young pirate and his crew to glory, riches, and infamy.

Here was a world that cast you as a small player, powerful and rich only on a relative scale and constantly at the mercy of the great winds of history. As a privateer, you were vulnerable to the ever-shifting allegiances of the huge empires around you—able to thrive by picking off individual ships while your local governor turns a blind eye, but always at risk of ruin if they should change their mind.