The trapdoor key was a quest item given to the player by Pikkupstix during the Wolf Whistle quest. The player could use it on the trapdoor in Pikkupstix's house in Taverley to access the Summoning obelisk beneath the house. When the trapdoor had been unlocked and opened, the key would disappear from the inventory. The player could then climb-down the trapdoor.
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