We sidle across the dark beams of the lock onto the little island in the middle of the canal. You reach out your hand to mine to help me down. Thanks. It’s 4am and the clouds are just beginning to ripen with a pinkish light from the east. We shuffle to the end of the island and down the stone steps. There’s an enamel plaque of a rabbit with no ears, holding a grenade. I drop your heavy rucksack to the dirty floor, just a few inches above the sticky canal water. We wait as the dinghy inflates, and then, quietly, load it up with all our things and step aboard. It’s a six metre journey to the bridge. It almost doesn’t seem worth it. Beneath the southern arch, as promised, the door. You pull a long, delicate black key from your overalls. Just you wait.