Where the Sun Turns: Straddling the Tropical and Temperate Zones at Mojiang Tropic of Cancer Mark Park

The Geographic Wonder at 23°26' N

1.Located in the Mojiang Hani Autonomous: County of Pu'er City, Yunnan Province, the Mojiang Tropic of Cancer Mark Park serves as a monumental intersection of geography, astronomy, and ethnic culture. Situated approximately 260 kilometers from Kunming along the Kunming-Bangkok Highway, this park is built directly on the latitude of 23°26' North, the imaginary line that defines the northernmost limit of the sun's direct vertical rays on Earth. As one of the largest and most comprehensive parks of its kind in the world, it transforms an abstract geographical concept into a tangible experience. Visitors here have the unique opportunity to stand with one foot in the Tropical Zone and the other in the Temperate Zone, physically straddling the invisible boundary that dictates global climate patterns.

2.The Main Marker: Tower and the Shadowless Instant

3.The centerpiece of the park is the majestic: Main Marker Tower, which stands 23.26 meters tall, symbolizing the specific latitude of the Tropic of Cancer. The tower features a precise sighting hole at its apex. Every year on the Summer Solstice (around June 21st), a spectacular astronomical phenomenon occurs: the sun shines directly through this hole onto a small copper dot on the ground below. At this exact moment, vertical objects cast absolutely no shadow, marking the "turning point" of the sun before it begins its journey back south. The park is designed along a central axis called the "Road to Return," featuring a series of sculptures, sundials, and astronomical instruments that guide visitors through the evolution of human understanding of the cosmos, from ancient Hani worship of the sun to modern scientific geography.

The Home of Twins and Hani Culture

Mojiang is not only defined by its latitude but also by its mysterious reputation as the "Home of Twins." The phenomenon of twin births in this region is remarkably higher than the global average, a fact locals attribute to the magical properties of the Twin Wells (Shuangbaojing) located in the county. Legend has it that drinking the water from these wells blesses couples with twins. This unique biological mystery is celebrated annually during the International Twins Festival, which draws pairs of twins from all over the world to Mojiang. The park integrates this local lore with the vibrant culture of the Hani people, who revere the sun and nature. Throughout the park, visitors can see Hani architectural elements, totem poles, and stone statues that reflect the indigenous belief systems and their deep connection to the celestial cycles.

A Fusion of Science and Scenery

Beyond its scientific and cultural significance, the park is a scenic retreat set against the backdrop of the lush Yunnan mountains. It is a fusion of garden art, astronomical education, and folk tourism. Walking up the mountain along the marked line, visitors pass through different zones representing the "Five Elements" and various planetary themes. Whether you are a geography enthusiast keen to witness the "Upright Pole with No Shadow," a traveler exploring the ancient Tea Horse Road that runs through Pu'er, or someone seeking the blessing of the Twin Wells, this park offers a multifaceted journey into the mysteries of the earth and sky.