In 1955, Professor Yao Zhan, head of the Department of Civil Engineering at Yunnan University, designed a seven-storey tower on the Donglu Campus in Kunming. Rising 26 metres to its roof and 30 metres including its steel-frame pinnacle, he intended the structure to serve as a utility water tower, pumping water to the adjacent Chemistry, Biology, and Physics laboratories. To signal the start of classes, campus workers hung a discarded oxygen cylinder on the top floor. They struck this heavy metal cylinder with a mallet, sending a sharp, metallic clang echoing across the campus. This daily ritual prompted students to call the water tower the Clock Tower.

The tower stands as a quiet sentinel near the stone marker of the First Astronomical Point of Yunnan. The masonry tower rises twenty-six metres, its rough brickwork cool to the touch. Above this brick base, a steel framework reaches its final thirty-metre peak, catching the warm orange glow of the setting sun. This visual phenomenon is celebrated as "Clock Tower Catching the Twilight." At the base of the tower, the massive, mottled trunk of a century-old London planetree—the largest of its species in Kunming—stretches its branches upward, its leaves rustling in the mountain breeze.

The tower represents a fusion of practical engineering and academic life. In 2005, Kunming recognized its architectural value by listing it as a Historical and Cultural Heritage Protected Building. In 2011, the city designated it as a Municipal Cultural Relics Protection Unit alongside the surrounding science buildings. Visitors can still walk the shaded paths around its base, hearing the wind through the ancient planetree and imagining the industrial ring of the oxygen cylinder that once measured the hours of Yunnan's early scientists.