Borderlands 4 is set on Kairos, which is a vast, beautiful world (haha), filled to the brim with warring factions, fauna that wants to eat you, and is under the rule of the Timekeeper. There are four distinct zones or regions that you will be able to explore seamlessly (as there are no loading screens).
These include places that are as diverse and colorful as the Licensed Parts System. That being said, here's everything you need to know about every open-world region in Borderlands 4.
List of all open-world regions in Borderlands 4
Fadefields

With radiant beaches, whimsical rolling hills, and verdant forests, the Fadefields appear to be a temperate paradise, or so it would seem. Ruled by Idolator Sol, a ruthless individual who only wants to please his beloved Timekeeper. He would do anything to stay in power, including controlling food and supplies, without caring about the people under his care.
This region may just be the main farming area for players looking to stack up on gear or just gain a lot of experience. By the looks of it, there's a lot to explore, and it could take quite some time to uncover all POIs. This is also the easiest region by the looks of it.
Terminus Range

In stark contrast to Fadefields, this zone is a mountainous region that features limited greenery and snow-capped areas and is home to the Augers. The towering peaks of this region are as unsympathetic as they are cold and hold both ancient and man-made secrets.
There's bound to be a lot of vertical exploration, which will give you a chance to try out the new Movement Abilities in Borderlands 4. There are bound to be enemies that can seemingly scale heights as well; you may want to keep an eye on the horizon while moving about.
You will also encounter Vile Lictor here, who keeps a grip on the population and exploits them to mine Ordonite. When you do encounter the boss, be prepared to fight an enemy of epic proportions. Make use of weapons from different manufacturers to even the odds.
Carcadia Burn

This desolate piece of land features pockmarked sandscapes and jagged desert canyons. This occurred following the celestial cataclysm, when Elpis teleported into Kairos' orbit. This region is occupied by the Rippers, who will answer to their Queen's every beck and call.
Despite this region being all but drained of life, the Rippers siphon resources to fuel their fight against the Order. Caught in the crossfire, the Electi fight a dire battle for survival; however, things are not going in their favor.
Dominion

This zone, Dominion City is is an unwavering monument to the Timekeeper's absolute control. It towers above Kairos and serves as a constant reminder of the Timekeerpers' hold on things. This is where brave Vault Hunters will face their toughest battle yet.
Elpis (Unconfirmed)

While the aforementioned regions have been confirmed to be fully explorable, some rumors suggest Elpis may also feature exploration. Of course, this is not set in stone, but given that the Moon is what got the ball rolling, by breaking the Timekeeper's perfect paradise, it may play host to POIs of its own.
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