The Chenhu Migratory Bird Observation Tower is a 19.8-metre observation tower in the Chenhu Wetland bird sanctuary near Wuhan, China. Designed by Xiang Architects, the structure consists almost entirely of staircases arranged as a double helix, forming a continuous route through the tower. Each staircase ends at a short balcony-like platform with a glazed section, creating 24 staggered viewing points along the ascent. The staircases also form the primary structural system, replacing a conventional central core. Twenty-four standardized prefabricated elements wrap around a central three-metre-wide void, with counter-rotated steel braces supporting the structure.
The tower is entirely clad in steel, giving the observation point a metallic exterior across its staircases, platforms, and structural elements. The sanctuary surrounding the tower becomes home to more than 100,000 migratory birds each winter, with the elevated platforms positioned to provide views across the marshland. The double-helix circulation separates ascending and descending routes while maintaining access to the staggered platforms.
Image Credit: Chen Hao
Why This Trend Is Growing
- Helical Viewing Architecture
- Double-helix circulation transforms stairways into structural and experiential features, opening possibilities for compact landmarks that manage visitor flow while creating continuous scenic engagement.
- Prefabricated Eco-tourism Structures
- Standardized modular components support faster construction in sensitive natural areas, creating opportunities for lower-impact tourism infrastructure with repeatable design systems.
- Distributed Observation Platforms
- Staggered viewing points across a vertical route redefine the single lookout model, enabling more immersive crowd distribution and varied perspectives in wildlife destinations.
Industries Being Reshaped
- Architecture
- Structural staircases and coreless tower designs signal new potential for expressive public infrastructure that merges circulation, engineering, and visual identity.
- Eco-tourism
- Wildlife sanctuaries can benefit from elevated, low-footprint visitor experiences that balance habitat protection with premium nature-based observation.
- Modular Construction
- Prefabricated steel elements highlight scalable opportunities for durable outdoor structures that can be assembled efficiently in remote or environmentally sensitive sites.
