They slipped into the crypt door shortly before the cathedral closed at 7:30 and descended to the chapel. Darwin had been right. A pry bar a meter and a half long leaned against the back wall. Eyrún picked up a plastic pail with two hammers and various chisels, and they headed back to the lava tube. Ten minutes later, they reached the wall.

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“How do you want to do this?” she asked.

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“It’s thinnest in the arrowslit, and we can use the slit for leverage,” he said, hefting the bar in both hands, its weight about half that of the barbells he used in the gym.

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The wall’s builders had staggered the half-meter-wide rectangular blocks for strength, using half-width blocks to make a clean gap for the arrowslits. Combined with the angles cut in the blocks for the archers, Darwin figured this was the wall’s weakest point. Eyrún concurred.

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The arrowslits were four blocks high with the half-width blocks in the second and fourth positions from the slit’s bottom. He inserted the chiseled end of the pry bar into the arrowslit against the second-position block and wedged it tight. Facing the wall, he pushed the bar as if performing a chest press. A series of pops sent chips flying toward Eyrún.

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“Ah!” she yelled. Darwin paused while she moved behind him. Three more pushes broke off more small chunks. “Stop. Look.” A centimeter-wide gap had opened between blocks.

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Darwin removed the pry bar from the arrowslit and shoved the chisel point in the gap. Eyrún rapped the pry bar’s end with a hammer, causing it to bite deeper. Darwin wiggled the bar and the gap opened. They worked this process of hammering and prying until the smaller block was nearly free. Darwin then rammed the bar repeatedly into the block until it fell away on the opposite side of the wall.

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Sweat beaded on both their foreheads and they stripped off their jackets. They looked in the larger opening, but there were no signs of bodies. Eyrún took up the pry bar against the other half-width block. Pushing was more awkward at shoulder height, and Darwin helped until a gap exposed, then she worked the bar in the opening while he hammered. When the block had turned sufficiently, they used the bar together to slam the block out of the wall.

 

“Wooo! I won’t miss the gym this week after all,” she panted, hands on knees.

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One full-sized block remained in the middle of the arrowslit, sticking out like a sideways tooth. They agreed that removing this last block would give them enough room to pass through. Fortunately, its length created better leverage as it pivoted forty-five degrees with much less effort than required on the first two blocks. Unfortunately, it needed more work to pound it free of the wall, but three minutes later, it dropped behind like the others. They took a break, sitting against the tube wall, and drank from water bottles.

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“I need a shower,” said Eyrún.

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“We went three weeks without one in the Iceland tube,” he said.

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“Oh, God. That was disgusting.”

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“Well, we can go back now. Take a shower and return in the morning,” he said.

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“Are you kidding? No way we’d get any sleep. I’m game if you are,” she said, nodding at the opening.

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He jumped up and stuffed gear from the duffels into his pack: batteries, climbing kit, water bottles, and energy bars. She joined him and when they were ready, squeezed through the opening. “What’s so funny?” she asked, looking at his face-splitting smile.

“I thought of the first time we met. You went underground first. It felt like I was competing to keep up.”

​

“You were. Hand me my pack, slowpoke.”