Context:

This is within my homebrew D&D world, set in a desert kingdom called Akkar.

Water is key to life, and in the desert this is an ironclad law. Without water, there can be no city. And, as the water goes, so must the city.

Oasis That Walks is named for the rather unusual water source that is the lifeblood of the city. While it is plentiful enough to support a multitude, every so often (ranging from six months to a couple of years) it suddenly shifts position, moving short or long distances away, though always within a couple days' travel. When this happens a new water source suddenly springs up in what was barren desert, and the old one quickly dries up (or is gathered into containers for the journey to the new site). When the water moves, so too must the city, resulting in a great flurry of activity as people pack possessions up for travel, possibly abandoning items, and move to the new site. There, people set up once again and the city is reborn in a new configuration. It is said that one can visit the Oasis That Walks a dozen times and never see the same city twice.

The city is thronging hive of tents and portable structures, with everything designed to be taken down in a hurry and moved when the need arises. The people of Oasis That Walks are primarily tradesmen, craftsmen, and herders—the shifting nature of the water makes farming essentially impossible, and so the city relies on food imports as well as a fair amount of food foraged from the desert wilds. Nevertheless, it is an important hub, as there is little water around it and travelers from many directions must pass through.

Oasis That Walks produces a great deal of high quality engraving, painting, jewelry, and other crafts which do not require a great deal of infrastructure. They've achieved sufficient renown with jewelry and engraving that their works are valued even a tremendous distance away—they can import gold and gems from the Dwarvenhome mountains, and produce works that the dwarves prize, which is no small feat.

Standard concepts of land ownership don't have much relevance to Oasis That Walks. Each time the city is remade, space is allocated largely on the basis of who arrives first, along with some negotiation and tradition that dictates positioning. Disputes are resolved by the mukhtar, and the ultimate process of settling out who is situated where can take weeks. Further, the haphazard organization tends to favour the wealthier (who can afford animals to move their belongings at a faster speed, and thus are likely to be among the first arrivals), and can also result in some very disorganized structures that make little sense from a practical perspective. Typically those with many animals will also make multiple trips, being hired to cart goods for those who otherwise lack the ability. It is considered a noble act of charity to make the last trip one to move goods for those who otherwise could not afford to do so, though in practice many do not make an entire trip for this and may instead count it as having performed the trip if they simply fill out any empty carrying capacity on their last trip with charitable transport. Although it does happen, using the resettlement as an opportunity to steal from one's neighbours is considered a grave transgression, and even an accusation of same is a serious matter—the sorts of things that lifelong grudges are born of.

There is always a major celebration that takes place about two weeks after the oasis moves (on the first weekend day after two weeks have passed), as people who are now resettled (or in the process of doing so) gather and drink and dance into the late hours around bonfires lit in the desert.

The locals generally consider someone to be a 'proper' resident of Oasis That Moves once they've gone through two moves, though the total number is sometimes used as a means of establishing credibility. Some people carve, paint, or otherwise make a mark on their home to indicate the number of times they've had to move it. This is also one of the rare times when the Elixir of Madness is consumed--a fermented beverage made from a hallucinogenic desert cactus and generally consumed diluted to the strength of a strong beer. Some drink it and wander in the night, staring up at the stars. The truly brave, or those seeking some spiritual understanding may drink it at full purity, where it is approximately 40% alcohol, and the hallucinations it brings are intense. Typically this is done in small groups, away from others, and with secrecy being maintained between those who participate. Most, however, know better than to touch it—diluted or not.