Cerro Prieto is the primary headquarters and mercantile of the Esqueleto, a chem cartel and trader union, situated in Chihuahua City, Chihuahua, Mexico in 2281. Burrowed into the northeastern hills of the city at the center of Mexican Highway 45, Cerro Prieto is the hub of commerce, barter and refuge along the trail between Ciudad Juárez and El Paso.
The city-state is surrounded by powerful walls known by the citizens as the "Paredes de Bloqueo" or by most as the "Great Blockades". It borders the entire encampment, spanning roughly two kilometers in length. Construction began eighty years prior in 2201, the same year the ancestors of the Esqueleto resettled their community at Cerro Prieto. Over the decades, the walls have grown and expanded excessively, and now tower menacingly, compared to when it was first constructed to keep out geckos.
Subsequent citizens have always added to the wall. It has been continuously built upon, refurbished, and increased in size since it was originally erected, making it significantly bigger than it was originally. The Esqueleto continuously build upon it day after day, following tradition, without ever really stopping to consider whether increasing the height was necessary or if it was secure enough. They themselves do not know why they do it, they also do not know for what they are really preparing for, except continuity.
While living in an ever-changing, fanatical atmosphere 24-7, all kinds of weird rituals appear to boost morale and to help them not think about the absurdity of their situation: due to this, it can be assumed that the Esqueleto have been conditioned into regularly building the walls to give them purpose and something to do; to keep them sane and non-existential. Subdued.
The cartel has literally uprooted every tree, hauled every rock, and unhinged every scrap of metal in a mile radius around the city-state. Thus, scouts have a clear 360-degree view of the entire surrounding area. It is impossible to sneak up on the fortress, so the element of surprise is ruled out: the only way to attack is to cross the distance without being killed in the process.
Without their protective walls, the city-state would not have existed for so long and be so prosperous as it is. The entrance to Cerro Prieto is over a small bridge connecting the area to the mainland of Chihuahua City.
Due to their imbued value of Pre-War ammunition, the Esqueleto would rather not use firearms to defend against a siege, opting to use more archaic forms of repellents: Rocks and rubble, boiling tar and mud-water, poisonous gases and smoke, decayed carcasses, and even long makeshift spears known as pikes.