TARDIS tin-mine
From Tardis Wiki, the free Doctor Who reference
The Doctor's TARDIS had a tin mine. After replacing the Time Vector Generator and restoring the TARDIS's interior dimensions, the Doctor hoped "nothing got too scrambled" and that Polly "wouldn't like to find her room at the bottom of the tin-mine". When Ben asked about the mine, the Doctor expressed surprise that he hadn't shown the two of them the mine yet. (PROSE: Invasion of the Cat-People)