Here are some names that you could use or that perhaps might inspire something.
Shambhala In Tibetan Buddhist tradition, this kingdom is hidden somewhere in the Himalayas; Theosophists regard it as being on the etheric plane above the Gobi Desert and as being the home of the governing deity of our planet Sanat Kumara.
Axis MundiThe axis mundi is a ubiquitous symbol that crosses human cultures. The image expresses a point of connection between sky and earth where the four compass directions meet. At this point travel and correspondence is made between higher and lower realms.
Khan TengriUighur, literally "King Heaven", translated as "Lord of the spirits", or "Lord of the sky"; or Turkic translated as "Ruler of Skies", "Ruler Tengri".
HelThe old Old Norse word Hel derives from Proto-Germanic *khalija, which means "one who covers up or hides something", which itself derives from Proto-Indo-European *kel-, meaning "conceal". It is also the norse land of the dead and the name of the godess that resides there, like Hades in Hades.
NoxIn Greek mythology, Nyx ("night", Nox in Roman translation) was the primordial goddess of the night.
DisIn Dante Alighieri's The Divine Comedy and Virgil's Aeneid, Dis is the City of the Dead.
Hypogeum Means "underground", from Greek hypo (under) and gaia (earth). It usually refers to an underground, pre-Christian temple or a tomb.
MeruMount Meru (also called Sumeru i.e the "Great Meru") is a sacred mountain in Hindu and Buddhist cosmology as well as in Jain cosmology, and is considered to be the center of all the physical, metaphysical and spiritual universes.
DeliriumAcute confusional state.
LengLeng (or Y'Pawfrm e'din Leng) is a fictional cold arid plateau in the Cthulhu Mythos, whose location seems to vary entirely from story to story. The Plateau of Tsang, referenced by H. P. Lovecraft and other authors, is probably a region of Leng. Abdul Alhazred describes it as a place where different realities converge, which might explain why its precise location cannot be pinned down.
Qatu NashuAkkadian: qātu našû; to raise the hand; to rise; to plunder.
UriasThe common Romanian-language designation of giants.
Tamoanchan Is a mythical location of origin known to the Mesoamerican cultures of the central Mexican region. In the mythological traditions and creation accounts of peoples such as the Aztec, Tamoanchan was conceived as a paradise where the gods created the first of the present human race out of sacrificed blood and ground human bones which had been stolen from the Underworld of Mictlan.
EreshgalSumerian: "great lady".
ElysiumIn Greek mythology, the Elysian Fields, or the Elysian Plains, were the final resting places of the souls of the heroic and the virtuous.
KiengirSumerian: ki-en-ĝir "Land of the Lords of Brightness".
KemetThe name of Ancient Egypt in Egyptian. Means "The Black Land".
Atum-kaAtum is an important deity in Egyptian mythology. His name is thought to be derived from the word 'tem' which means to complete or finish. Thus he has been interpreted as being the 'complete one' and also the finisher of the world, which he returns to watery chaos at the end of the creative cycle. As creator he was seen as the underlying substance of the world, the deities and all things being made of his flesh or alternatively being his ka: "spirit".
UrdIn Norse mythology, Urðr (Old Norse "fate") is one of the Norns. Along with Verðandi (possibly "happening" or "present") and Skuld (possibly "debt" or "future"), Urðr makes up a trio of Norns that are described as deciding the fates of people.
Itchan KalaItchan Kala is the walled inner town of the city of Khiva, Uzbekistan. World Heritage Site. Nothing to do with any element, but the name sounds cool.