They climbed into the tight cave. Headroom wasn’t a problem, but the tunnel was so narrow it was difficult to walk without scraping their shoulders. The cave climbed steeply, and, with space so tight, their footing was uneven. A wrong step could twist an ankle. Linda was concentrating on her movements yet still aware of danger, and she spotted the trip wire well before she was going to trigger it.

It was a thin filament of copper that stretched across the tunnel at the level of her shins, with one end secured to the wall with an iron screw and the other vanishing up into the gloom ahead. She pointed it out to the others and cautiously stepped over it.

The sharply ascending tunnel ended another hundred feet from the trip wire in a small room with a low ceiling. They had to crawl under a wooden trestle built at the tunnel’s exit. The wire wrapped around a metal lever built into a device that would fall back when it was tripped. This in turn would release a carved-stone ball sitting on the angled cradle. The ball was about three feet around and weighed in at half a ton. A direct hit, after rolling and bouncing down the shaft, would crush a man flat, while a glancing blow would surely break bone.

“We should trigger it,” Mark said, mostly because the kid in him wanted to watch the stone hurtle down the tunnel.

“Leave it,” Alana said. The archaeologist in her hated the idea of disturbing what was the find of her career.

“We’ll compromise,” Linda said. She plucked a stone from the ground and wedged it under the boulder. Even if someone hit the trip wire and the lever were released, the rock would prevent it from moving.

There were a few other man-made items in the room—a battered wooden chest missing its lid, an empty sword scabbard for one of the Barbary pirate’s wicked scimitars made of beaten brass, a couple lengths of rope, and a half dozen thin metal shafts Mark identified as ramrods. They took the opportunity to change out their flashlight batteries, and started exploring further.

Three different tunnels branched off from what they called “the boulder room.” They explored one tunnel without incident and were halfway down the second one when Linda placed a foot on a hidden trigger. There was just the tiniest give under her foot, but she knew they were in trouble.

Just under the surface of the sandy passage, a wooden board had been buried and cleverly concealed. Her weight rasped a piece of steel against flint under the plank to produce enough sparks to ignite a fuse. The cask of gunpowder was secreted farther in the hole, and contained enough explosive to kill all four of them.

Linda jumped back instantly and, in a tackle that would have done a pro football player proud, pushed her three companions back until the whole pile of them went down. But the blast never came. Instead, the powder ignited and burned unevenly, a flaring, sputtering cauldron of fire that filled the tunnel with noxious white smoke. In the two hundred years since the trap had been set, the powder’s acidity had eaten through the wooden cask, so when it lit there was nothing to contain the fire and cause an explosive detonation.

“Everybody all right?” Linda asked when the last of the powder had burned itself out.

“I think so,” Alana answered, stifling a cough.

“I feel like I just went three rounds with Eddie in his dojo,” Eric replied, rubbing his ribs where Linda’s shoulder had hit him. “I never knew someone so small could hit so hard.”

“Amazing what a little adrenaline can do.” She stood and brushed herself off. “The fact that this tunnel’s booby-trapped tells me we’re on the right path.”

They kept going, and the tunnel started climbing. There was no way of knowing how deep they had gone or where they were in relation to the riverbank, but all of them felt they had to be getting close.

There was more evidence that people had spent a greater amount of time in this part of the cavern. There were marks in the sand coating the ground where men had walked, men who had constructed the elaborate traps they had already passed. Twice more, Linda stopped the party to check the ground, but they found no additional hidden bombs.

The tunnel turned sharply. Linda peered around the corner before committing herself and came up short. Around the bend stood an iron door embedded in the rock. The metal had a reddish hue, a tracery of rust having formed from exposure to damp air when the river still flowed. There was no lock or keyhole. The door was a featureless slab of metal, so they knew the hinges must be on the other side.

Linda dropped to one knee to dig through her pack.

Mark moved until he was directly in front of the door, spread his arms wide in a theatrical pose. “Open sesame,” he intoned. The door didn’t budge. He glanced over at Alana. “You know, I kind of thought that would work.”

“This will.” Linda straightened, holding a block of plastic explosives.

She used a piece of cardboard torn from a box in her first-aid kit to slip between the door and jamb to determine which side it hinged from and set her charges over the hinges. She selected a pair of two-minute timing pencils and rammed them home.

“Coming?” she called sweetly, and the four of them retreated fifty yards back down the tunnel. The distance muted the blast, but the pressure wave hit with enough force to ripple their clothes.

When they returned, the door had been blown from its hinges and tossed ten feet into the next section of the tunnel.

Unlike the claustrophobic nature of much of the cave, the chamber they found themselves standing in was vast. It was longer than the reach of their flashlights and equally broad. The ceiling lofted forty or more feet over their heads. Much of the cave was limestone like they’d been seeing since entering the earth, but the wall to their right was a vast mound of rubble, the debris blasted over the cave’s entrance when Henry Lafayette started his long journey home.

On the left side of the cavern ran an elevated platform that looked like it had once served as Suleiman Al-Jama’s pier. And tied to it, canted slightly because its keel rested on the ground and wasn’t floating as it should, was the infamous pirate’s ship, the Saqr.

Her mast had been lowered and her rigging stowed in order to enter the cave, but otherwise she looked fully capable of sailing once again. The dry air had perfectly preserved her wooden hull. She was facing away from them, so the mouths of her stern long guns looked like enormous black holes.

On closer inspection, as they peered down on her from the quay, they could see where she had sustained damage during her running battle with the American ketch Siren.

Chunks of her bulwarks had been blown apart by cannon shot, and there were a dozen places where fire had scorched the deck. One of her guns was missing, and, judging from the damage around its emplacement, it had exploded at some point during the battle and was lost over the side.

“This is absolutely amazing,” Alana said breathlessly. “It’s a piece of living history.”

“I can almost hear the battle,” Mark agreed.

There was so much more to explore, but for several minutes the four of them stared down on the corsair.

A flicker of movement to his right caught Eric’s attention and broke him from his reverie. He cast the beam of his light back to the remnants of the mangled doorframe just as a figure slipped through. He was about to shout a challenge when an assault rifle opened up ten feet from the first man’s position, its juddering flame winking in the darkness.

In the half second before he reacted, he saw several more gunmen in the uneven light. Bullets filled the air around them when more weapons opened up.

The four had no idea how Al-Jama’s people had found them so quickly, but the fact was clear. They had arrived with almost three-to-one superiority, and more ammunition because they were prepared for a fight, and now they controlled the only way out of the cave.