Earth

Earth, also referred to as "The Ground", is the original home of humanity. The planet had been affected by radiation for 97 years after a devastating nuclear apocalypse. After the Ark's life support systems were found to be failing critically, the 100 were sent to the surface in a last ditch attempt to determine if Earth is habitable again. The 100 are now living on the planet along with the Grounders, as well as the rest of the Sky People from the Ark.

Environment
Over the course of a century, Earth has become a very different place in the wake of the Nuclear Apocalypse that left much of the world devastated and drove mankind to near extinction. Ecosystems have changed, landscapes have been reshaped, and life has evolved.

The infrastructure that had existed throughout the land had been mostly destroyed. The little human infrastructure that survived, such as bridges, monuments and buildings, now lay in ruin. Nature has reclaimed the land, the scenery observed by the 100 indicates little signs of the devastation.

Major Locations

 * The Ark
 * The Delinquents' Camp
 * Mount Weather
 * Arkadia (formerly Camp Jaha)
 * Polis
 * Tondc
 * Dead Zone

Art Supply Store
Also known as Finn's Bunker, it is the name given to a bomb shelter discovered by Finn Collins. The bunker's original purpose was to serve as a shelter from nuclear bombs in the case of an apocalypse but the owners never made it. The Delinquents used it for supplies as well as a place to take shelter.

Because of the instability of the Delinquents' society, Finn convinced Clarke to keep the bunker a secret in order to have a place to hide if the needs arose. In Murphy's Law, when Murphy was out to get Charlotte, Finn and Clarke hide Charlotte down in the bunker. After Finn and Clarke fall asleep, they wake up to find that Charlotte ran away. Later, Clarke and Finn sleep together in the bunker. After Raven arrives on earth, Clarke takes Raven to the bunker in His Sister's Keeper to look for a transmitter to fix the radio. Raven found a remote-controlled car and used it for parts.

After capturing Delano in Reapercussions, Finn takes Bellamy, Murphy, Monroe, and Sterling to the bunker to question Delano, ending in Finn executing him. Finn returns with Clarke to the cave one last time in Fog of War when they flee from Acid Fog, coming face-to-face with Delano's corpse.

Lincoln's Cave
In His Sister's Keeper, Lincoln brings Octavia back to his cave to treat her injuries. After Lincoln is captured and tortured by the Delinquents, Octavia helps him escape and he returns to his cave. Octavia meets up with Lincoln again in his cave in Unity Day and together with Finn Collins, they arrange the bridge meeting between Clarke and Anya. In I Am Become Death, Octavia finds Lincoln in his cave, packing up his belongings. He asks her to leave with him but she ultimately refuses and decides to stay behind with the Delinquents. Lincoln returns to the cave in We Are Grounders (Part 2) after outrunning Reapers and runs into Finn who convinces him to use the Reapers as a distraction to help the Delinquents during the final battle.

Oil Rig


Located away from the mainland, the Floukru‎‎ live on the oil rig.

Seen in Join or Die, Red Sky at Morning

Other Minor Locations

 * Becca's Island
 * Mount Weather Mines
 * Philpott Dam
 * Lincoln Memorial
 * Eden's Pass

Residents
According to Becca, about 6.5 billion people were killed in the aftermath of the Nuclear Apocalypse. However, some survivors remained, these included the ancestors to the Grounders, the Mountain Men, and the Sky People. The Mountain Men took refuge in Mount Weather and the Sky People survived in space for 97 years isolated from their former natural environment.

Current

 * Grounders
 * Sky People

Former

 * The Grounders (the Ark) (left to go live on the Ark)
 * Mountain Men (deceased)
 * Reapers (deceased)
 * A.L.I.E. (deceased)

Trivia

 * Earth is still irradiated, but the Sky People are immune due to growing up around solar radiation.