Svartalfheim, also known to its natives as Niðavellir, is one of the Nine Realms of the World Tree and the home of the Dwarves. In Norse cosmology, Svartálfar "Black Elves", "Swarthy Elves", sing. Svartálfr, also called Myrkálfar, "Dark Elves", "Dusky Elves", "Murky Elves", sing. Myrkálfr), are beings who dwell in Svartalfheim (Svartálf[a]heimr, "home of the Black-Elves"). Both the Svartálfar and Svartálfaheimr are primarily attested in the Prose Edda, written in the 13th century by Snorri Sturluson. Scholars have noted that the Svartálfar appear to be synonymous with the Dwarfs and potentially also the Dökkálfar ("Dark Elves"). As Dwarfs, the home of the Svartálfar could possibly be another description for Niðavellir ("dark fields"). While many would compare Midgard to Svartalfheim, both realms have in reality little in common. Where Midgard is a cold, poor, wild and inhospitable place, Svartalfheim is on the contrary a warm, moist and yet colorful realm traversed by vast expenses of magnificent azure water. Small but well built cities, spouting geysers and vast network of mines are also typical of the dwarven realm. The mastery of the Dwarfs over their home world is demonstrated by the numerous water systems, industrial machinery and ingenious mechanisms they built all over the landscape. The Dwarven realm is also rich in resources such as pure iron, whose quality is such that is known in the other realms as "Svartalfheim Steel". The incredible smithing skills of the Dwarfs as well as the wealth of their home world eventually caught the attention of Odin. It wasn't long before Svartalfheim eventually fell under the control of the Aesir, who not only effortlessly crushed the Dwarven resistance but also managed to shamelessly exploit the resources - including high quality weapons - of the realm for their own use. Foreigners aren't welcome in Svartalfheim as the realm has become loyal to Odin, even though it is mostly out of fear of Asgard's power.
This region was the region that was adjacent to Nifelheim and extended into the Middle East regions of Turkey and Syria, leading to the realm of the Vanir and Vanaheim which were the royal caste of Dark Elves under Enlil's command known as the Tribes of Israel. The key difference is, in knowing the history of the Draco and which hybrids were created when and how. The early pitch black evil Elves were the Canaanites, but from their lineages, after mixing into some of the human tribes, the corrupted Draco lineages took on the human energies and when they took on the Beta creating the B- Vampire Tribes of Israel, they became extremely refined by comparison to the original violent and evil Canaanites whom they either subjugated or destroyed. Enlil told them to annihilate them all, but some liked to keep them as pets to do their work for them. Although due to their influence this lead to many factions of Dark Elves being led astray by Canaanite influences, whilst others went on a conquest to exterminate them all.
Once a land of beautiful springs, and fountains, with tiny highly advanced technological enclaves carved into the sides of cliffs and mountains leading to the underground tunnel networks, stonemasonry and structures were everywhere, powered by Dwarven technologies. The Dwarves often found amusement in fighting with the the Dark Elves / Vanir, but rarely getting the better of them. Their entire goal was to humilate and torment the other faction, rarely kill them, for that wasn't as as much fun as trying to outsmart the other and other stealing the other's goods / property or swindling them out of it with shady dealings, of which their tribes keep up on this tradition to this very day, believing that a fool and his money are soon parted ways. The Dwarves once thrived after being cast out by both the Humans and the Draco. Possessing the knowledge of the original Titans in some cases, through the preservation of their ancient texts, they were able to recreate much of the old Atlantean technology for themselves and sought to use it to their advantage. So Nifelheim, like most of the regions, is not just a single location but a large complex structure of enclaves / hives and the networks connecting them that extend from one country / continent to another. The land of Svartalfheim is actually that of the halfling Beta human tribes and the O- Draco who created halfling Hybrids similar to their fair complexion counterparts in the West which was A1+ / O- hybrids.
The Dark Dwarves were similar in their mechanical abilities, but the Dark Dwarves often used runic inscriptions to create vastly superior weapons of war, which is what drew Odin to them initially. Aside from the weaponsmithing, the Dark Dwarves were known for using some of the rejected arts to create artificial life through their Golems, which would be on par with our modern day Androids. With his obsession for immortality, Ilvaldi sought to turn himself into a machine God, replacing the flesh with steel and the blood with oil. His work became the foundation for the concept of creating a new Satanic Hive of animated drones, that would be considered neither alive, nor dead. This is why why Odin cursed Nifelheim and all those who sought out his work on immortality through artificial means, knowing that in their attempt for immortality, their would lose their life to the Mists and become what they sought, part of an immortal legend and story for the fools who dared defy the Creator and the Cycles.