Mount Pelée is the volcano that fills the north of Martinique. On the morning of 8 May 1902 it sent a cloud of burning gas down its own slope and killed the 28,000 people of the port below in minutes. The crater that fired it is a walk now. You come out on the lip of Étang Sec, green and quiet, usually filled to the brim with cloud, with the dome that grew there in 1929 on the far side. Getting up there means root-laced steps and wooden staircases through fern and bamboo, cool and dripping while the coast below bakes. You are climbing into the cloud layer this summit wears almost every day. Above the trees the ridge pinches to a few kilometres wide under your boots, and on a clear morning the Atlantic swell breaks on one side of you while the Caribbean lies flat and glassy on the other. Those mornings are rationed: the cap thickens by mid-morning, and February to April are the only dependable months.
Saint-Pierre came back smaller, a fishing town on black sand where boats lie at the foot of the ruined theatre and the volcano closes every street. At dusk its cloud cap turns pink and orange and the whole thing looks harmless. The ships that burned at anchor are still on the floor of the bay, and divers go down to them. The wet ravines above hold the Martinique volcano frog, the only member of its family on an oceanic island and found on no other slopes. In the winter after the eruption a spine of lava climbed out of the crater as much as fifteen metres a day, until it stood 300 metres high with about the volume of the Great Pyramid. It shed slabs until it was rubble. Two people in the town lived. One was Ludger Sylbaris, locked up six days earlier for knifing a man in a brawl. His punishment cell still stands: a half-buried stone box with no window, aired by a grating in the door that happened to face away from the mountain.