Midgard

Miðgarðr (Old Norse: ᛘᛁᚦᚴᛅᚱᚦᛦ [ˈmiðˌɡɑrðz̠]; meaning "Middle Enclosure", "Middle Garth", "Middle Earth", and "Middle Yard", anglicised as Midgard) is one of the Nine Realms of Norse mythology. It is the realm of humans (mortals) and is the only realm fully visible to mankind, though other realms intersect with it.

Miðgarðr is bordered by Niflheimr to the north and Múspellsheimr to the south. It is surrounded by an ocean inhabited by the world-encircling Jǫrmungandr, often referred to as "Miðgarðsormr" or the "Midgard serpent". It is also connected to Ásgarðr, the realm of the Æsir, by the Bifröst.

Ragnarök
The world of Miðgarðr is destined to be destroyed during Ragnarök; the end of the world. Jǫrmungandr will arise from the ocean and poison the land with his venom. Opposing forces of Æsir, Vanir and other allies will fight Loki and the Jǫtunn, amongst other forces, at Vígríðr. Resulting casualties will include many of the gods and their enemies (Jörmungandr and Þórr will be slain by each other). The world will then be engulfed in the flames of Surtr and sink into the sea, only to rise anew.