Perched atop the Niujijiaobian (Ox Horn Edge) peak in the Huairou district of northeastern Beijing stands a sentinel of stone and brick, enduring the lash of the mountain wind.
Just months ago, the hollow watchtower, its mid-level featuring a central chamber surrounded by a corridor, lay buried under roughly five meters of debris, before a meticulous monthslong excavation by the Beijing Institute of Archaeology brought it back to light.
Marked as Watchtower 117 of the Jiankou Great Wall, it spoke volumes about Ming Dynasty (1368-1644) engineering and the lives of the soldiers who manned it, according to Shang Heng, associate research fellow at the Beijing Institute of Archaeology.
"The most surprising element is the large footing at the base of the watchtower. On the southeast corner, this footing extends outward in 15 distinct layers. It's massive. This discovery means the total height of the watchtower post-excavation is nearly double what we initially estimated," Shang explains, adding that the watchtower features the largest such footing discovered in the Jiankou section.
"This fully demonstrates the technical approach to the Great Wall's construction: to minimize cutting into and altering the natural mountain terrain."
Jiankou is a rugged and largely unrestored section of the Great Wall that was built along steep mountain ridges. It is known for its dramatic scenery, sharp angles, and original brickwork. Because Jiankou has been left mostly in its natural state, it offers a rare glimpse into the Great Wall's authentic historical conditions.
Strategically placed at the highest point where the wall turns, Watchtower 117 features access gates on its western and southern sides.
"Given the steep terrain, the western gate is particularly imposing, with large stone steps and a raised platform leading to it," Shang adds.
Within the central chamber of Watchtower 117, archaeologists uncovered a perfectly preserved stele commemorating its establishment in the first year (1573) of Emperor Wanli's rule during the Ming Dynasty.
Made of bluestone, the rounded-top tablet stands 95 centimeters tall, 50 cm wide, and 9 cm thick. Its 253 characters of inscribed regular script, framed by intricate vine and grass patterns, serve as more than just a marker.
"This stele not only precisely dates the construction of Watchtower 117 but also provides crucial materials for studying the organizational structure and management of Great Wall construction projects, the formation and evolution of the Jiankou section in the Ming Dynasty, and serves as a benchmark for understanding the relationship between the architectural form and age of hollow watchtowers," Shang notes.
It is the second such Wanli-era stele found at Jiankou, with the first discovered at Watchtower 156 in the west section.
Watchtower 117 is a key finding from the fifth phase of archaeological work on the Jiankou section.
The project was approved by the Beijing Municipal Cultural Heritage Bureau and the National Cultural Heritage Administration.
It is intended to support conservation work on this section of the Great Wall by providing a scientific basis for formulating protection plans, while also contributing to a deeper exploration and understanding of the Wall's historical and cultural significance.
The project focused on the eastern segment from watchtowers 117 to 122 along the ridge at Xizhazi village in Huairou.
From March to October, archaeologists excavated watchtowers 117, 118 and 119, as well as the connecting walls.
This year's excavation work yielded over 300 artifacts, including weapons, architectural components, daily utensils, and a wealth of carbonized remains.
Moving west from Watchtower 117, the findings at Watchtower 118 breathe with everyday life.
This vaulted, hollow watchtower is well-preserved and contains the largest kang (heated brick bed) discovered so far at Jiankou, Shang says.
More captivating were two inscribed bricks. One bears the characters "North Kiln: 550 jin (traditional Chinese unit of weight of 500 grams)", the other, "One Row: 79 jin". These words were scratched into the wet clay before firing, likely using a stick or nail.
"These bricks served as identifiers, but they record weight, not quantity, which challenges our assumptions," Shang notes.
"It might offer new material for researching the production organization of Ming-era brick kilns."
On a brick used in a floor atop the tower, archaeologists found a whimsical poem, also written pre-firing.
"The poem's theme revolves around wine and melancholy, ending with 'a 3-year-old child's hair turns white'," Shang reveals.
"This graffiti suggests the craftsmen weren't illiterate. They possessed a certain level of cultural refinement," he says.
These findings make Watchtower 118 a record-breaker for holding the most inscribed bricks found at Jiankou, according to the archaeological team.
The excavation of Watchtower 119, at the foot of "Ox Horn Edge", reveals a time closer to the Ming Dynasty's end.
