The Unmarked Mouth

You almost miss it. A breath of wind parts a curtain of ivy at the cliffside, and there — a fourth tunnel, narrower than the others, its lip darkened as if scorched by something the rock itself remembers.

You step closer. The air pouring out is wrong: sweet, like overripe pears, and beneath that a metallic tang that prickles the small hairs on your arms. Your borrowed lantern flickers without any draft to blame. The map in your pocket suddenly feels heavier, as though it has been waiting all morning for exactly this.

Three tunnels behind you. One ahead that no one drew. What do you do?