Hepmonaland

In the Dungeons & Dragons roleplaying game, Oerth /ˈɔərθ/ is the name of the fictional planet on which one of the earliest campaign settings, the World of Greyhawk, is located. Oerth has an axial tilt of 30 degrees, which would cause greater seasonal temperature variation than on Earth, were it not for wizardly and divine magic that shifts weather patterns to be more favorable to the populace (at least the god-fearing folks).

Oerth is detailed in the 1980 version of the World of Greyhawk Fantasy Game Setting, which covers less than a quarter of the landmass of Oerth.

According to the paper by Gary Holian in Oerth Journal, Oerth's circumference is about 42,024 km, and its radius measures 6,714 km, about 1% more than that of Earth. There is no flattening of the planet sphere due to rotation, and divine power is again hinted at.

Oerth has at least four continents, the largest of which is Oerik, lying mainly in the Northern Hemisphere. Southeast of Oerik lies the much smaller landmass of Hepmonaland, lying in the tropics. Hyperboria, also called Telchuria (after Telchur, the god of winter), lies at the north pole, while an unnamed fourth continent lies in the southern hemisphere. Oerth is thought to have four oceans, including the Solnor Ocean, the Dramidj Ocean that circles Telchuria, the Ocean of Storms south of Oerik, and the Sea of Thunder encompassing Polaria.

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Wikipedia