The main RuneScape Wiki has an article on: King Black Dragon lair
The Old School RuneScape Wiki also has an article on King Black Dragon lair.

Dungeon entrance ladder, Member's Gate and lesser demons.

Part of Lava Maze dungeon contains the lever to KBD lair. There are multiple poison spiders in the lever area.

The King Black Dragon lair is a small dungeon located under the Lava Maze in the Wilderness. It can be accessed from the cage filled with lesser demons west of Lava Maze, and then by using the lever in the Lava Maze dungeon. It is the home of the strongest monster in RuneScape Classic, the King Black Dragon.

The dungeon itself is not in the Wilderness, only the entrance is. Therefore teleportation is allowed inside the lair, and players are safe from player killing once they make it down the ladder.

Overview of the lair.

Map of the Lair.

Monsters

King Black Dragon.png Poison Spider.png
King Black Dragon 6 Poison Spiders

Quests

  • None

Item spawns

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