Chapter Sixty-Three: The Rebels Lay Siege to the City

The Sui Tongguan fortress was built much grander and more imposing than the Han Tongguan city, relying on even more perilous terrain. What gave the Sui Tongguan fortress its imposing momentum and additional danger was chiefly the Forbidden Ravine to its southeast. The Forbidden Ravine was, in truth, a wide mountain gorge that could also be called a riverbed between the mountains, though it was usually dry unless a heavy rain fell. When it rained heavily, the Forbidden Ravine became a river.

The ravine was on average six or seven zhang wide, and even at its shallowest, it was more than a zhang deep. The Sui fortress was built against the western edge of the ravine. Any rebels massing to the southeast would have to cross the Forbidden Ravine before reaching the city walls. The city walls of Sui Tongguan rose three to four zhang high, and together with the depth of the ravine, they formed a barrier some six to seven zhang high—roughly twenty meters. There was little footing at the base of the walls, and few places where scaling ladders could be set. Along the western edge of the ravine, the protruding mountainsides bristled with twelve beacon towers, forming a chain that jutted from the wall and could strike at besiegers as they crossed the ravine.

Yet now, many corpses, bloated and rotting in the heat, had not been cleared from the ravine, giving off a nauseating stench. The piled bodies diminished the natural defense of the ravine—some sections were now less than a zhang high, so two men standing together could help each other up to the western edge. The rebels would certainly seize upon this, concentrating forces to assault the southern gate and wall from the direction of the ravine.

The east gate of Sui Tongguan was set some distance from the ravine, with steep mountains lying between the city wall and the gorge. For the rebels to climb these mountains and attack the wall would be as difficult as scaling the sky itself. Thus, the only feasible approach was the winding road leading from the city gate; yet, about five or six hundred paces from the wall, the terrain by the ravine and the Yellow River bank was gentle enough to allow the massing of large numbers of troops—beyond the reach of arrows or catapults from above.

This flat stretch by the Yellow River outside the east gate would serve as a staging ground for a large-scale rebel assault. The rebels would surely launch their main attack from the east and south gates, though only limited numbers could reach the base of the walls.

The north gate of Sui Tongguan was, like that of Han Tongguan, set against the Yellow River and flanked by treacherous mountains. The rebels could not amass large forces there—at most, a hundred or so could attempt an assault, posing little real threat to the defenders unless they all fell asleep or abandoned their posts. Nor could the rebels muster enough men at the foot of the wall to threaten the defenders with arrow fire.

The west gate faced away from the rebel approach, serving as the entrance and exit for those coming from Chang’an—unless the rebels attacked from that direction.

Whoever commanded the siege of Tongguan, if approaching from Luoyang, would certainly launch the main assault from the east and south gates. The rebel deputy commander, Cui Qianyou, decided just that. Once Li Qian and Cheng Wei arrived with their three thousand-odd remaining troops at the east and south gates, he immediately gave the order to attack—Cheng Wei to assault the east gate, Li Qian the south.

Upon receiving the order, both Li Qian and Cheng Wei commanded their hastily assembled troops to attack the walls in waves without delay.

As the two generals gave their orders, their hearts were heavy with tragic resolve. They knew these few thousand vanguard troops were destined to perish beneath the walls of Tongguan.

Li Qian gave his order first. At his command, the first group of several hundred soldiers rushed forward with scaling ladders into the ravine. The eastern side of the ravine was not a sheer drop, but a relatively gentle slope, so the attackers could descend without much effort. But the western side was steep—without ropes or ladders, few could climb it, and those who tried might fall to serious injury or death.

The scaling ladders carried by the first wave were meant to help them reach the western edge of the ravine, then be used to scale the wall itself. Just as Li Qian’s men, shields raised, rushed down and began to set their ladders, Cheng Wei’s troops also launched their assault on the east gate.

Hundreds of rebel soldiers, shields held high, charged up the winding road, howling as they began their attack. Cui Qianyou himself led the next waves, rapidly reinforcing the assault. He intended to repeat the tactics used at Han Tongguan: relentless waves of attacks, heedless of casualties, to exhaust the Tang defenders and deplete their arrows. He did not expect to capture the wall while the Tang soldiers still had strength, but to wear them down until, spent and out of arrows, they could be overwhelmed.

Too much time had been wasted that morning at Han Tongguan; neither Cui Qianyou nor An Qingxu had much confidence they could take Sui Tongguan by day’s end. Yet An Qingxu had issued a death order: no matter the cost, the city must fall, and the fighting would not cease until it was taken.

Cui Qianyou also ordered his men to attack the walls in endless waves, with no pause. The assault was to continue, even through the night, regardless of Tang defensive measures or fire attacks—so long as even a part of the fortress remained untaken, the battle would not stop.

Standing atop the east gate tower, Yang Xi gazed coldly at the rebels massing in the distance. He watched as they launched attacks of several hundred men each at the east and south gates, even before all their troops had assembled. Instantly, Yang Xi understood the rebel commander’s strategy: the same as at Han Tongguan—sacrifice lives to exhaust the defenders’ strength and arrows.

He did not worry for lack of arrows—fresh supplies had been brought in over the past two days—but he was deeply concerned for the stamina of his men. Most of the garrison had retreated from defeat at Lingbao; even the three thousand he had brought from Chang’an were weary. The only truly fresh troops were the three thousand left in reserve by Geshu Han. Overall, the defenders were a tired force. The rebels, though also exhausted, had enough numbers to attack in waves. If reinforcements did not arrive and his own numbers could not be replenished, Yang Xi knew their fate might be to die with the city.

Yet he still believed that, with his more than ten thousand men, he could hold out against the rebels until help arrived.

Watching coldly, he saw the first few hundred rebel soldiers come within range of the ballistae on the walls and immediately gave the order himself: “Ballistae, fire!”