Heroes of Prophecy
The planes that surround Eberron are at the same time closer and more remote than they are in other settings. With most people lacking both the capability and reasons for visiting them, very few natives of Eberron have even considered visiting another plane. The orbit of the planes about the Material Plane strengthens this pattern, as another plane is accessible only rarely.
However, at the same time, the planes of Eberron have much more direct effect on the prime material than in other settings. The other planes orbit the prime material, approaching and receding from it and waxing and waning in their influence upon the prime material plane. Any commoner can tell you that fire burns brighter and longer when Fernia is close, storms accompany the close approach of Kythri, and poor harvests occur when Lamannia is distant. Any common people could probably also name basic inhabitants of some planes (though this knowledge would be limited to generalizations like “fire things” from Fernia and so on). Moreover, Eberron has seen a number of extraplanar invasions over the millennia, and thus its people are not quite as surprised as they might be when strange creatures cross over from other planes into Eberron. While the daelkyr invasion from Xoriat occurred ten millennia ago, everyone has heard of it, and it is not unsurprising to find outsiders lurking in the strangest places throughout the world.
In terms of the planar names used in the Player’s Handbook, Eberron’s planes of Dolurrh—the realm of the dead—and Mabar—the endless night, a region of shadows and despair—are entered via the Shadowfell; the Feywild is an ancient name for Thelanis, the faerie court.
Manifest zones are places outside the typical planar cosmology where a plane’s energy pervades a certain location on the Material Plane, affecting the traits of the region. Well known manifest zones include the Syrania manifest zone within which Sharn is built, a Lamannia manifest zone deep within the Eldeen Reaches, and a massive Risia manifest zone in the Frostfell far to the north.