Pathnode
Pathnodes are viatic pocket planes that connect the eidopoles of Eidecia. While many pathnodes are populated, they have far fewer inhabitants than the eidopoles, and most people of the Cities think of the pathnodes as only areas that must be passed through to travel between cities, and perhaps as places where food is grown and other resources are harvested. Some æalogists prefer to consider the pathnodes as really the fundamental planes of Eidecia, and the eidopoles as mere excrescences that connect them with other cosmoi, but this is a minority view, and in any case the matter is somewhat artificial; the eidopoles and the pathnodes are both connected parts of Eidecia, and there are no good grounds for considering one objectively more fundamental than the other.
Topology
Setting aside their connections to the eidopoles, topologically, all pathnodes, without known exception, are glomungules. Their gravitational fields have two singular points, the zenith and the nadir. The vectors have a component pointing from the zenith to the nadir, which is largest midway between the two, at the pathnode's equator, and smallest near these points. A perpendicular component is largest near the singular points and diminishes to zero at the equator, though even near the zenith and nadir it remains finite. The maximum magnitude of this component isn't necessarily the same from pathnode to pathnode, or even between the nadir and the zenith within a pathnode. The relative angle of this perpendicular component on opposite sides of the equator also varies. In any case, generally the pathnode's lower half—that is, the part on the same side of the equator as the nadir—is filled with earth and dirt or other materials that constitute the "ground" (or, in some cases, with water or other fluids). The ground doesn't necessarily fill exactly half of the pathnode; it may be lower or higher than the equator; but it usually is fairly close to half.
Less technically, what this all amounts to is that the ground surface of a pathnode is toric in shape; walking far enough in any direction will eventually bring a traveler back to his starting point. The pathnode also has a maximum altitude (the height of the zenith); a lighter-than-air object released within a pathnode will tend to rise toward the zenith and then circle around it. There is likewise a maximum depth that can be reached downward, and toward which all objects will tend to fall (only to circle around it when they reach its proximity), but since in most pathnodes the vicinity of the nadir will be filled with earth, this is not usually a concern.
The connections to the eidopoles introduce an additional complexity, forming a discontinuity both in the gravitational field and in the glomungular shape. Essentially, the eidopolis and the pathnode are connected by a very short wormhole, usually situated at the level of the ground surface. From each side, the entrance will appear to be roughly spherical in shape, with the area beyond the wormhole appearing oddly compressed and distorted, but it is possible to walk through from any direction and emerge on the other side. In most cases, the entrance will be surrounded by walls, with one or more doors or passageways leading through. From the city side, the entrance to the pathnode will appear to be a sort of walled-off area, as if the pathnode were a courtyard within the city affected by multum in parvo. From the pathnode side, the wall will appear to surround an inside-out version of the city itself. There may or may not be a roof over the entrance; if there is, then opposite sides of the roof will be visible from the eidopolis side and the pathnode side. If there is no roof, it is possible to fly or through objects over the walls into or out of the pathnode.
Geography
Few pathnodes are more than a few hundred kilometers across at their widest dimension, and many are significantly smaller than that. This adds to their convenience for traveling between the eidopoles, since even at a walking pace most sojourners will be able to pass through any but the largest pathnodes in a matter of days, and the smaller pathnodes can be traversed in mere hours.
The contents of the pathnodes vary as much as the eidopoles. In fact, some æalogists have tried to associate each pathnode with a particular theme or principle like the eidopoles, but all such attempts have proven arbitrary and unfruitful. In any case, while many pathnodes are terrestrial, others can be decidedly alien and daunting. Of the terrestrial pathnodes, many, particularly the smaller ones, comprise only a single terrain, containing nothing more than an endless grassland or forest. Others show more variety, however, with patches of swamp, mountain, or other terrains mixed in, perhaps including great ravines, tall cliffs, or other barriers to passage. (Of course, where convenient to travel between eidopoles, bridges, tunnels, and ramps will no doubt have long ago been constructed to traverse these obstacles.) The stranger pathnodes can contain virtually anything: silvery webs stretching through a void, precarious ribbons of stone snaking high over seas of lava, metallic mazes haunted by monsters of steel. Naturally, the more fremd and forbidding the pathnode's terrain, the less traffic it tends to get, though if it provides a useful enough shortcut between two eidopoles there are bound to be those who brave its bizarreries.
Inhabitants
Though no pathnodes have nearly the population density of the eidopoles, they are not all uninhabited. Some of the pathnodes, especially those given largely over to farming, contain one or more small villages, seldom with more than a thousand inhabitants each. For the most part, these villagers are certainly aware of the existence of the eidopoles, and are used to seeing travelers between eidopoles pass through their nodes. Some of the villagers, indeed, may be former eidopolitans themselves, who for whatever reason decided to retire to (or hide out in) a pathnode; others are descendents of such, and have heard much of the eidopoles from their parents. Even some of the villagers with no eidopolitan ancestors within recent memory are likely to have visited the Cities from time to time. There are, also however, many insular visitors whose families have dwelt in their pathnode from time immemorial, and who are content to live out their lives circumscribed in that small area.
Many pathnodes, even those otherwise without permanent residents, have inns catering to travelers who want a comfortable place to stop on their journey. Some courageous entrepreneurs have even succeeded in establishing inns in some of the weirdest and most hazardous pathnodes... just as long as those pathnodes have enough wayfarers to keep them in business. These inns vary in quality and amenities, from simple two-room boarding houses to, in some of the most traveled pathnodes, great hotels with large staffs and many stories, outfitted with the latest magical and technological comforts and conveniences. In most cases, smaller pathnodes have only one inn, and in larger pathnodes the inns are spaced a full day's journey apart. There are some locales, however, where multiple inns compete for lodgers, and those who pass that way have their choice as to which to stay in.
Resources
Many pathnodes with suitable soil and climates are used for farming and herding, providing much of the food to sate the eidopoles' enormous appetites. Some of the larger and wilder pathnodes also harbor exotic game hunters can sell for a high price. Aside from food, plants, animals, fungi, and other life forms are also raised to provide leather, fibers for textiles, dyes, spices, and various other chemicals and materials.
A few pathnodes have proven to have valuable minerals, and have been heavily mined. Others are filled with water that is piped into eidopoles that lack sufficient sources of their own. Still others yield magical substances or strange, one-of-a-kind objects and materials that may enrich those who discover and lay claim to these esoteric resources.
Connections
The pathnodes' connection to the eidopoles is well known, and is what gives them their name: they are thought of as nodes that form paths between the cities. Short of leaving Eidecia altogether and somehow journeying from the world where one eidopolis is set to the world of another, there is no known way to travel between eidopoles without going through at least one pathnode. Conversely, however, there seems to be no way to travel between pathnodes without going through at least one eidopolis, so there is something complementary about their arrangement.
Explorers have recently discovered, however, that the eidopoles may not be all the pathnodes connect to. Deep underground passages like the ones leading to the eidopoles have been found that connect to huge cavern systems which, as far as explorers have thus far been able to determine, don't necessarily seem to belong to either pathnodes or eidopoles. Similarly, invisible portals have been discovered high in the skies of some pathnodes that seem to connect to unfamiliar airy expanses likewise distinct from the previously known parts of Eidecia. These areas have only recently have come to the serious attention of æalogists, and so far remain little explored, though there are those who believe that understanding the Catachore and the Caelichore, as these "new" planes have come to be known, would lead to a much greater understanding of the nature of Eidecia itself, and perhaps that of all existence.