«Black Iron Palace» (黒鉄宮(こくてつきゅう), Koku Tetsu Kyū?) is a palace on the 1st Floor of Aincrad, located within the Town of Beginnings, in Sword Art Online and New ALfheim Online. It is the largest facility within the city[1] and one of the most famous landmarks within Aincrad.[2]


The large rectangular[2] black palace is located north of the Teleport Gate plaza of the Town of Beginnings[3] and is encircled by large castle walls and a moat.[1] The palace was assembled with black glossy pillars and metal boards,[4] had a tall and large front gate, iron floors and an abnormally high ceiling.[2] The air within the palace is significantly cooler than outside.[4]

There was a Hidden Dungeon under the palace, likely to be unlocked by fulfilling a certain condition on the higher floors.[1] It was also used as a headquarters[5] and prison by the Aincrad Liberation Force (The Army), usually for «Orange Players».[6] Players violating the Harassment Prevention Code may be teleported to the Black Iron Palace's prison, if the victim chooses to select this option on the system prompt that appears when the system detects a breach of ethics.[7] Players can also be sent to the prison with the use of Corridor Crystals, the destination of which is set for the prison.[8]


In the Beta version of Sword Art Online, the palace housed the game's re-spawn point, called the Room of Resurrection. However, in the official version of the game, the Room of Resurrection was replaced by the Monument of Life, which kept track of the deaths of the SAO players.[5] When Aincrad was later incorporated into New ALfheim Online, the Monument of Life was replaced with the Monument of Swordsmen, keeping track of the names of the participants of successful Labyrinth Boss raids.[9] The monuments are placed in the hall right after entering through the main gate. Only this hall was open to the public at all times, while the deeper parts of the palace were under the control of the Aincrad Liberation Force by November, 2024.[1]




Aincrad Locations Navigation Bar
Teleport Gate
Floor Notable locations and landmarks
1 Town of BeginningsBlack Iron Palace, Hidden DungeonMonument of Swordsmen[Navbar 1]Monument of Life[Navbar 2]Chamber of Resurrection[Navbar 3]TolbanaHorunka Village, Medai Village
2 Urbus, Urbus Teleport Gate Plaza, Marome Village, Taran Village
3 Forest of Wavering Mists, Zumfut, Zumfut Teleport Gate Plaza, Dessel
4 Rovia, Rovia Teleport Gate Plaza, Bear Forest, Yofel Castle, Usco Village, Caldera Lake
5 Karluin, Karluin Teleport Gate Plaza, Mananarena, Shiyaya
6 Stachion, Stachion Teleport Gate Plaza, Suribus, Ararro, Castle Galey, Lake Talpha
7 Monster Arena[Navbar 4]
8 Frieven Village, Frieven Teleport Gate Plaza
9 Dark Elf Queen's Castle[Navbar 5]
10 Thousand Snake Castle[Navbar 6]
11 Taft, Taft Teleport Gate
19 Ralberg, Ralberg Teleport Gate, Hill of the Cross, Griselda's Tomb
20 Sunshine Forest
22 Coral Village, Coral Teleport Gate Plaza, Forest House K4, Lake Outside Coral Village
24 Panareze, Panareze Teleport Gate Plaza
25 Giltstein, Giltstein Teleport Gate Plaza, Former location of the Knights of Blood Headquarters
27 Ronbaru Town, Ronbaru Teleport Gate
28 Wolf Plains
35 Forest of WanderingMishe, Mishe Teleport Gate Plaza
39 Nolfret, Nolfret Teleport Gate Plaza, Former location of the Knights of Blood Headquarters
40 Jaileum, Jaileum Teleport Gate Plaza
46 Ant Hill
47 Floria, Floria Gate Plaza, Hill of Memories, Forest of Giant Flowers
48 Lindarth, Lindarth Teleport Gate Plaza
49 Myujen, Myujen Teleport Gate Plaza
50 Algade, Algade Teleport Gate Plaza
55 Granzam, Granzam Teleport Gate Plaza, Knights of Blood Headquarters, West Mountain
56 Pani, Divine Dragon Alliance Headquarters
57 Marten, Marten Teleport Gate Plaza
59 Danac, Danac Teleport Gate Plaza
61 Selmburg, Selmburg Teleport Gate Plaza
65 Old Castle Labyrinth
66 Old Castle Labyrinth
72 Ozmalt, Ozmalt Teleport Gate Plaza, Agarla Village
74 Kamdet, Kamdet Teleport Gate Plaza
75 Collinia, Collinia Teleport Gate Plaza
100 Ruby Palace
  1. Only in New ALO
  2. Only in the SAO official service
  3. Only in the SAO Beta
  4. According to Kirito in Progressive Volume 1, Rondo of a Fragile Blade, Part 1
  5. According to Kizmel in Progressive Volume 3, Barcarolle of Froth, Part 7
  6. According to Kirito in Progressive Volume 1, Aria of a Starless Night, Part 14
ALfheim Online Locations Navigation Bar
Midgard New Aincrad - See Aincard Location Navigation Bar for locations in new Aincrad
World Tree Alne - Virtual Lab (Floating City) - Yggdrasil City
Alfheim Ancient Forest - Butterfly Valley - Swilvane - Legrue Corridor - Legrue - Thule Island - Undersea Temple
Jötunheimr Great Void - Thrymheim
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