Erwt

Geography
Erwt is a flat disc-shaped world, and only the top surface is known to be inhabited.

There are 12 Landscapes with 2-4 sovereign countries each. Each country has 1-2 sizable cities but generally most of the population is rural. The Landscapes are arranged in a circle (clockface), and are defined by a common geography and often culture.

The clockface is surrounded by a world sea, and there is a large inner sea in the middle. The world ocean is very rough, the outer coast windy, rocky,  and inhospitable. Little or nothing is out there: aside from smugglers and outlaws, there's no reason to brave these elements. Those fish that can be caught are unpalatable and often poisonous. Besides, Here Be Monsters. No roads lead to the edge of the world.

The inner sea is dramatically different. Here are fishing fleets, this is where the inner-side powers field their armadas (such as they are at an 11th-century technology level), trade galleons ply the blue-green waves, and pirates and scallywags of every type and colour chase their dreams of fortune and infamy.

Each landscape is approximately 1000 miles wide. The entire Erwt is around 1.3 million square miles in area. For reference, this is about 1/300th of the land area of Earth. Including the inner sea, it's over 2.5 million square miles.

"West" is counterclockwise, "east" is clockwise. That makes "north" oceanward, and "south" seaward.

There are dragons that inhabit the landscapes, each of which tie in to the natural environment that dominates it.

Landscapes
XII Gutreal - mountains (Gutwith, Rocliffe, Brocklye, Rea)

I Weald - forests (Greater Lysternum, Bannoch, Eyrum)

II Samala - arctic (Samala, Aurala)

III Ennobel - plains (Belwidth, Overweck, Opperfak, Gerterchek)

IV Isolet - archipelago (Lettish, Ardich, Oerik)

V Quipmen - fungal wastes (Pmonia, Qualtso)

VI Aether Waste - aether waste (nothing lives here)

VII Exympor - volcanic wastes (Ix, Ympire, Der Totem)

VIII Arif - deserts (Alquarest, Zhuma, Bal-Biliad)

IX Ardellia - archipelago (Pellonia, Bellia, Istennel, Indosel)

X Indonardel - jungle (Indonel, Ardel)

XI Mangali - grasslands (Quri, Ular)

The Island - a small landmass apart from the Landscapes, at the exact centre of the Sea, equidistant from all Landscapes.

Passage of Time
When it's noon in the north, it's midnight in the South. The sun moves counterclockwise around the world. Days are 24 hours long like on Earth. The sun visibly rises and sets over neighbouring Landscapes. From its surface, t he world appears spherical (like earth) because light travels in a curve due to aether diffraction.

Every 60 days is one month, making days like minutes and months hours. 12 months is one year. So, seasons on Erwt last twice as long as on Earth. Just like days and nights, moon phases and seasons travel around the clockface in a counterclockwise fashion. As on Earth, the sun sets in the west and rises in the east.

The 60-day months are divided into 5-day "weeks" (12 quindums), or 12-day segments (5 duxums). Both systems are used interchangeably, depending on what is most convenient for the speaker or listener. Each of these divisions also have names, which repeat every month. And of course, there are 5 "day" words for every day in the quindum, and 12 "day" words for every day in the duxum. All these words are very very old, from before the First Wizard arose, back when people worshiped the natural cycles of the Erwt.

Exploring the Back
At least 10 different countries claim to be the birthplace of Moshiach. There is no consensus, and the strong uncertainty and lack of substantial evidence in support for any particular claim is a primary reason this disagreement hasn't led to any significant armed conflicts. The first known record of his activities is a note of his presence on an exploratory expedition on the inner sea, in search of a more economical traverse across the sea between Lysternum in the Great Weald and Kairah in Arif than along the coast. The vessel was a specially built trireme, using a new timekeeping aid which allowed precise navigation away from shore. It also happens to be the expedition that led to the discovery of the Island at the center of the inner sea, which many consider to be His first recorded miracle. The Island is interesting in itself because it's the only place on Erwt where magic doesn't work. The Aether is thin and feeble, and wizards cannot get a grip on its subtle fabric, failing to perturb its structure and compel phlogista to imbue. There is a clear natural spring on the Island, a wide and deep sinkhole, feeding fresh groundwater into the soil, making the Island an oasis in the salty inner sea.

The outer sea has not seen any mundane exploration, and the few wizards who have attempted research projects outward have either not met with any progress, or disappeared without a trace. If you were to embark on such a foolish journey, perhaps hoping that the winds would calm away from land, and that the high seas would settle off the continental shelf, you would find your assumptions were hopelessly mistaken. The waves only go higher, the winds only more powerful. As the distance to land grows, the skies darken, the air grows cold and thin, screaming a terrible hurricane song, as the sea forms wall after giant wall. At some point, certain physical limits are passed, and the explorer finds himself caught irrevocably by the winds, or beneath the crushing black waves. In the roaring silence, burning hot if not for the numbing cold, in an airless crushing void of blinding darkness, falling weightlessly, he finds that somehow his life is sustained beyond his last breath. Slowly, his senses adjust and he finds himself looking through the ethereally shining night in which the Erwt floats eternally. The familiar stars and planets are all there in abject clarity. In fact, he discovers he can discern any arbitrary detail on their varied surfaces, which were previously thought to be featureless points of light. Turning his gaze back to Erwt, he is met by a strange and wondrous sight: the reverse side of the world he knows to be his home. An enormous clock face, luminescent, with baroque feathery details, the size of an entire world. At this point in time, our hypothetical explorer realizes that this is the real world, infinitely grander than anything conceivable, unimaginably beautiful, impossibly intricate. The Aether is the universe of the gods, and the Erwt is but an accident, an afterthought, no, just dust collecting on the backside of a wall clock, and all the lives of all the beasts and men are but mites, and the great forests and fields of Erwt are but mold polluting this pristine mechanism with its spores. A bright spring morning in the Weald, with birds a-twitter and bursting blossoms, is just half past six on this cosmic clock, but that simple datum here is more significant and filled with more depth and meaning than a thousand spring mornings on Erwt.

Once the shock of the awe fades, the curious explorer discovers there are a whole slew of dials and arms beyond the usual set indicating time. The lengths of the main arms are exactly in proportion to the Golden Ratio, the curling details on the face and frame carved in Fibonacci spirals. He will also discover that the clock is connected to a myriad fine fibers, which vibrate musically at the beat of the clockwork mechanism. These filaments extend in gentle, precise curves to other celestial elements. He wonders if perhaps those distant stars also harbor life, but only their pristine faces can be discerned, no hint as to what may hide behind. No method of winding the clock can be discerned, no pendulum is swinging; apparently, this clock is winding down until the end of time.

The hub of the clock, to which the main arms are mounted, is hollow. Perhaps that could lead through the face, to the back? Certainly returning by way of the outer rim is impossible, it is now clear that what appeared to be terrible storms were just decorative trim and bundles of vibrating fibres, but there is no immediately obvious way around it.